Check if we have a constructor
diff --git a/compiler.jx/src/org/apache/flex/compiler/internal/codegen/externals/pass/CollectImportsPass.java b/compiler.jx/src/org/apache/flex/compiler/internal/codegen/externals/pass/CollectImportsPass.java
index 28815f9..363eb2d 100644
--- a/compiler.jx/src/org/apache/flex/compiler/internal/codegen/externals/pass/CollectImportsPass.java
+++ b/compiler.jx/src/org/apache/flex/compiler/internal/codegen/externals/pass/CollectImportsPass.java
@@ -76,9 +76,12 @@
             }
         }
 
-        for (ParameterReference parameterReference : constructor.getParameters())
+        if (constructor != null)
         {
-            addClassImport(reference, getType(parameterReference));
+            for (ParameterReference parameterReference : constructor.getParameters())
+            {
+                addClassImport(reference, getType(parameterReference));
+            }
         }
 
         for (MethodReference method : methods.values())