diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/BooleanParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/BooleanParameter.java
index 2015a9821..eb1a278c5 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/BooleanParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/BooleanParameter.java
@@ -69,6 +69,16 @@ public class BooleanParameter extends AbstractParameter<Boolean> {
 		setValue(parseFromString(valueAsString));
 	}
 
+	/**
+	 * Sets the value to false
+	 * 
+	 * @see Parameter#clearValue()
+	 */
+	@Override
+	public void clearValue() {
+		this.value = false;
+	}
+
 	@Override
 	public String getType() {
 		return StrolchValueType.BOOLEAN.getType();
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/DateParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/DateParameter.java
index f99048aa6..197ad8e01 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/DateParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/DateParameter.java
@@ -71,6 +71,16 @@ public class DateParameter extends AbstractParameter<Date> {
 		setValue(parseFromString(valueAsString));
 	}
 
+	/**
+	 * Sets the value to 1970-01-01 (unix time 0)
+	 * 
+	 * @see Parameter#clearValue()
+	 */
+	@Override
+	public void clearValue() {
+		this.value = ISO8601FormatFactory.getInstance().getDateFormat().parse("-");
+	}
+
 	@Override
 	public String getType() {
 		return StrolchValueType.DATE.getType();
@@ -95,7 +105,7 @@ public class DateParameter extends AbstractParameter<Date> {
 	public static Date parseFromString(String valueS) {
 		return ISO8601FormatFactory.getInstance().getDateFormat().parse(valueS);
 	}
-	
+
 	@Override
 	public int compareTo(Parameter<?> o) {
 		DBC.PRE.assertEquals("Not same Parameter types!", this.getType(), o.getType());
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/DurationParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/DurationParameter.java
index 3f60d7a60..2d4fb25ef 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/DurationParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/DurationParameter.java
@@ -64,6 +64,16 @@ public class DurationParameter extends AbstractParameter<Long> {
 		this.value = value;
 	}
 
+	/**
+	 * Sets the value to 0
+	 * 
+	 * @see Parameter#clearValue()
+	 */
+	@Override
+	public void clearValue() {
+		this.value = 0L;
+	}
+
 	@Override
 	public void setValueFromString(String valueAsString) {
 		setValue(parseFromString(valueAsString));
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/FloatListParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/FloatListParameter.java
index cb641a5e6..84a9ce307 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/FloatListParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/FloatListParameter.java
@@ -67,7 +67,8 @@ public class FloatListParameter extends AbstractParameter<List<Double>> implemen
 			sb.append(iter.next());
 
 			if (iter.hasNext()) {
-				sb.append(VALUE_SEPARATOR);
+				sb.append(VALUE_SEPARATOR2);
+				sb.append(" ");
 			}
 		}
 
@@ -140,7 +141,12 @@ public class FloatListParameter extends AbstractParameter<List<Double>> implemen
 			return Collections.emptyList();
 		}
 
-		String[] valueArr = value.split(VALUE_SEPARATOR);
+		String[] valueArr;
+		if (value.contains(VALUE_SEPARATOR1))
+			valueArr = value.split(VALUE_SEPARATOR1);
+		else
+			valueArr = value.split(VALUE_SEPARATOR2);
+
 		List<Double> values = new ArrayList<>();
 		for (String val : valueArr) {
 			values.add(Double.valueOf(val.trim()));
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/FloatParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/FloatParameter.java
index b4efa6b25..eec001acb 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/FloatParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/FloatParameter.java
@@ -65,6 +65,16 @@ public class FloatParameter extends AbstractParameter<Double> {
 		this.value = value;
 	}
 
+	/**
+	 * Sets the value to 0
+	 * 
+	 * @see Parameter#clearValue()
+	 */
+	@Override
+	public void clearValue() {
+		this.value = 0.0D;
+	}
+
 	@Override
 	public void setValueFromString(String valueAsString) {
 		setValue(parseFromString(valueAsString));
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/IntegerListParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/IntegerListParameter.java
index da510ed81..e17bc29bc 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/IntegerListParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/IntegerListParameter.java
@@ -67,7 +67,8 @@ public class IntegerListParameter extends AbstractParameter<List<Integer>> imple
 			sb.append(iter.next());
 
 			if (iter.hasNext()) {
-				sb.append(VALUE_SEPARATOR);
+				sb.append(VALUE_SEPARATOR2);
+				sb.append(" ");
 			}
 		}
 
@@ -140,7 +141,12 @@ public class IntegerListParameter extends AbstractParameter<List<Integer>> imple
 			return Collections.emptyList();
 		}
 
-		String[] valueArr = value.split(VALUE_SEPARATOR);
+		String[] valueArr;
+		if (value.contains(VALUE_SEPARATOR1))
+			valueArr = value.split(VALUE_SEPARATOR1);
+		else
+			valueArr = value.split(VALUE_SEPARATOR2);
+
 		List<Integer> values = new ArrayList<>();
 		for (String val : valueArr) {
 			values.add(Integer.valueOf(val.trim()));
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/IntegerParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/IntegerParameter.java
index b1e17ca62..18b28d2f5 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/IntegerParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/IntegerParameter.java
@@ -69,6 +69,16 @@ public class IntegerParameter extends AbstractParameter<Integer> {
 		this.value = value;
 	}
 
+	/**
+	 * Sets the value to 0
+	 * 
+	 * @see Parameter#clearValue()
+	 */
+	@Override
+	public void clearValue() {
+		this.value = 0;
+	}
+
 	@Override
 	public void setValueFromString(String valueAsString) {
 		setValue(parseFromString(valueAsString));
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/ListParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/ListParameter.java
index a800fcdc3..25a43ff91 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/ListParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/ListParameter.java
@@ -18,12 +18,14 @@ package li.strolch.model.parameter;
 import java.util.List;
 
 /**
+ * A {@link Parameter} which supports a list of elements.
+ * 
  * @author Robert von Burg <eitch@eitchnet.ch>
- *
  */
 public interface ListParameter<E> extends Parameter<List<E>> {
 
-	public static final String VALUE_SEPARATOR = ";"; //$NON-NLS-1$
+	public static final String VALUE_SEPARATOR1 = ";"; //$NON-NLS-1$
+	public static final String VALUE_SEPARATOR2 = ","; //$NON-NLS-1$
 
 	/**
 	 * Adds a single value to the {@link List} of values
@@ -44,7 +46,7 @@ public interface ListParameter<E> extends Parameter<List<E>> {
 	public boolean removeValue(E value);
 
 	/**
-	 * Clears the list of values
+	 * Clears the list of values, i.e the list of values is empty after this call
 	 */
 	public void clearValue();
 
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/LongListParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/LongListParameter.java
index b3f55ad92..d6ee515a5 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/LongListParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/LongListParameter.java
@@ -67,7 +67,8 @@ public class LongListParameter extends AbstractParameter<List<Long>> implements
 			sb.append(iter.next());
 
 			if (iter.hasNext()) {
-				sb.append(VALUE_SEPARATOR);
+				sb.append(VALUE_SEPARATOR2);
+				sb.append(" ");
 			}
 		}
 
@@ -140,7 +141,12 @@ public class LongListParameter extends AbstractParameter<List<Long>> implements
 			return Collections.emptyList();
 		}
 
-		String[] valueArr = value.split(VALUE_SEPARATOR);
+		String[] valueArr;
+		if (value.contains(VALUE_SEPARATOR1))
+			valueArr = value.split(VALUE_SEPARATOR1);
+		else
+			valueArr = value.split(VALUE_SEPARATOR2);
+
 		List<Long> values = new ArrayList<>();
 		for (String val : valueArr) {
 			values.add(Long.valueOf(val.trim()));
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/LongParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/LongParameter.java
index f6d876155..d8a068cf2 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/LongParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/LongParameter.java
@@ -64,6 +64,16 @@ public class LongParameter extends AbstractParameter<Long> {
 		this.value = value;
 	}
 
+	/**
+	 * Sets the value to 0
+	 * 
+	 * @see Parameter#clearValue()
+	 */
+	@Override
+	public void clearValue() {
+		this.value = 0L;
+	}
+
 	@Override
 	public void setValueFromString(String valueAsString) {
 		setValue(parseFromString(valueAsString));
@@ -93,7 +103,7 @@ public class LongParameter extends AbstractParameter<Long> {
 	public static Long parseFromString(String valueS) {
 		return Long.valueOf(valueS);
 	}
-	
+
 	@Override
 	public int compareTo(Parameter<?> o) {
 		DBC.PRE.assertEquals("Not same Parameter types!", this.getType(), o.getType());
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/Parameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/Parameter.java
index 505afd54f..32db69d88 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/Parameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/Parameter.java
@@ -54,6 +54,11 @@ public interface Parameter<T> extends StrolchElement, Comparable<Parameter<?>> {
 	 */
 	public void setValue(T value);
 
+	/**
+	 * Clears the value, dependent on the concrete class
+	 */
+	public void clearValue();
+
 	/**
 	 * get the hidden attribute
 	 * 
@@ -141,12 +146,12 @@ public interface Parameter<T> extends StrolchElement, Comparable<Parameter<?>> {
 
 	@Override
 	public boolean equals(Object obj);
-	
+
 	@Override
 	public int compareTo(Parameter<?> o);
 
 	@Override
 	public Parameter<T> getClone();
 
-	public <U> U accept(ParameterVisitor visitor);	
+	public <U> U accept(ParameterVisitor visitor);
 }
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/StringListParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/StringListParameter.java
index 8ef1685af..18e1311b8 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/StringListParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/StringListParameter.java
@@ -67,7 +67,8 @@ public class StringListParameter extends AbstractParameter<List<String>> impleme
 			sb.append(iter.next());
 
 			if (iter.hasNext()) {
-				sb.append(VALUE_SEPARATOR);
+				sb.append(VALUE_SEPARATOR2);
+				sb.append(" ");
 			}
 		}
 
@@ -140,7 +141,12 @@ public class StringListParameter extends AbstractParameter<List<String>> impleme
 			return Collections.emptyList();
 		}
 
-		String[] valueArr = value.split(VALUE_SEPARATOR);
+		String[] valueArr;
+		if (value.contains(VALUE_SEPARATOR1))
+			valueArr = value.split(VALUE_SEPARATOR1);
+		else
+			valueArr = value.split(VALUE_SEPARATOR2);
+
 		List<String> values = new ArrayList<>();
 		for (String val : valueArr) {
 			values.add(val.trim());
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/StringParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/StringParameter.java
index 516ed4597..b6cd8979e 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/StringParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/StringParameter.java
@@ -25,10 +25,9 @@ import li.strolch.utils.dbc.DBC;
  */
 public class StringParameter extends AbstractParameter<String> {
 
-	public static final String UNDEFINED_VALUE = "-"; //$NON-NLS-1$
 	private static final long serialVersionUID = 0L;
 
-	private String value = UNDEFINED_VALUE;
+	private String value = "";
 
 	/**
 	 * Empty constructor
@@ -71,6 +70,16 @@ public class StringParameter extends AbstractParameter<String> {
 		this.value = value;
 	}
 
+	/**
+	 * Sets the value to the empty string
+	 * 
+	 * @see Parameter#clearValue()
+	 */
+	@Override
+	public void clearValue() {
+		this.value = "";
+	}
+
 	@Override
 	public void setValueFromString(String valueAsString) {
 		setValue(valueAsString);
diff --git a/li.strolch.model/src/test/java/li/strolch/model/ModelTest.java b/li.strolch.model/src/test/java/li/strolch/model/ModelTest.java
index 0ad641f3a..8aa8facce 100644
--- a/li.strolch.model/src/test/java/li/strolch/model/ModelTest.java
+++ b/li.strolch.model/src/test/java/li/strolch/model/ModelTest.java
@@ -421,6 +421,15 @@ public class ModelTest {
 		stringList.add("Hello");
 		stringList.add("World");
 		assertEquals(stringList, stringListP.getValue());
+		assertEquals("Hello, World", stringListP.getValueAsString());
+		stringListP.setValueFromString("a;b");
+		assertEquals("a, b", stringListP.getValueAsString());
+		stringListP.setValueFromString("a,b");
+		assertEquals("a, b", stringListP.getValueAsString());
+		stringListP.clearValue();
+		assertEquals("", stringListP.getValueAsString());
+		stringListP.addValue("a");
+		assertEquals("a", stringListP.getValueAsString());
 
 		IntegerListParameter intListP = bag.getParameter(PARAM_LIST_INTEGER_ID);
 		assertNotNull("IntegerList Param missing with id " + PARAM_LIST_INTEGER_ID, intListP);
@@ -429,6 +438,15 @@ public class ModelTest {
 		intList.add(10);
 		intList.add(15);
 		assertEquals(intList, intListP.getValue());
+		assertEquals("5, 10, 15", intListP.getValueAsString());
+		intListP.setValueFromString("4;45");
+		assertEquals("4, 45", intListP.getValueAsString());
+		intListP.setValueFromString("4,45");
+		assertEquals("4, 45", intListP.getValueAsString());
+		intListP.clearValue();
+		assertEquals("", intListP.getValueAsString());
+		intListP.addValue(55);
+		assertEquals("55", intListP.getValueAsString());
 
 		FloatListParameter floatListP = bag.getParameter(PARAM_LIST_FLOAT_ID);
 		assertNotNull("FloatList Param missing with id " + PARAM_LIST_FLOAT_ID, floatListP);
@@ -437,6 +455,15 @@ public class ModelTest {
 		floatList.add(11.0);
 		floatList.add(16.0);
 		assertEquals(floatList, floatListP.getValue());
+		assertEquals("6.0, 11.0, 16.0", floatListP.getValueAsString());
+		floatListP.setValueFromString("4.2;4.1");
+		assertEquals("4.2, 4.1", floatListP.getValueAsString());
+		floatListP.setValueFromString("4.2,4.1");
+		assertEquals("4.2, 4.1", floatListP.getValueAsString());
+		floatListP.clearValue();
+		assertEquals("", floatListP.getValueAsString());
+		floatListP.addValue(55.5);
+		assertEquals("55.5", floatListP.getValueAsString());
 
 		LongListParameter longListP = bag.getParameter(PARAM_LIST_LONG_ID);
 		assertNotNull("LongList Param missing with id " + PARAM_LIST_LONG_ID, longListP);
@@ -445,6 +472,15 @@ public class ModelTest {
 		longList.add(12L);
 		longList.add(17L);
 		assertEquals(longList, longListP.getValue());
+		assertEquals("7, 12, 17", longListP.getValueAsString());
+		longListP.setValueFromString("4;4");
+		assertEquals("4, 4", longListP.getValueAsString());
+		longListP.setValueFromString("4,4");
+		assertEquals("4, 4", longListP.getValueAsString());
+		longListP.clearValue();
+		assertEquals("", longListP.getValueAsString());
+		longListP.addValue(55L);
+		assertEquals("55", longListP.getValueAsString());
 	}
 
 	/**