diff --git a/jode/jode/type/ArrayType.java b/jode/jode/type/ArrayType.java
index 42a51cc..221a20b 100644
--- a/jode/jode/type/ArrayType.java
+++ b/jode/jode/type/ArrayType.java
@@ -175,6 +175,8 @@ public class ArrayType extends ReferenceType {
      * @return the middle type, or null if it is not necessary.
      */
     public Type getCastHelper(Type fromType) {
+	if (fromType.getTypeCode() == TC_NULL)
+	    return this;
 	Type hintType = fromType.getHint();
 	switch (hintType.getTypeCode()) {
 	case TC_ARRAY:
diff --git a/jode/jode/type/ClassInterfacesType.java b/jode/jode/type/ClassInterfacesType.java
index 0261ae7..8e08c3c 100644
--- a/jode/jode/type/ClassInterfacesType.java
+++ b/jode/jode/type/ClassInterfacesType.java
@@ -435,6 +435,8 @@ public class ClassInterfacesType extends ReferenceType {
      * @return the middle type, or null if it is not necessary.
      */
     public Type getCastHelper(Type fromType) {
+	if (fromType.getTypeCode() == TC_NULL)
+	    return this;
 	Type hintType = fromType.getHint();
 	switch (hintType.getTypeCode()) {
 	case TC_ARRAY: