diff --git a/Normalizer/src/de/bodden/tamiflex/normalizer/ClassRenamer.java b/Normalizer/src/de/bodden/tamiflex/normalizer/ClassRenamer.java
index 17830b1..ef39b59 100644
--- a/Normalizer/src/de/bodden/tamiflex/normalizer/ClassRenamer.java
+++ b/Normalizer/src/de/bodden/tamiflex/normalizer/ClassRenamer.java
@@ -49,7 +49,7 @@ public NoHashedNameException(String typeName) {
 	 * @return The bytecode containing the renamed references.
 	 */
 	public static byte[] replaceClassNamesInBytes(final Map<String, String> fromTo,	byte[] classBytes) {
-		ClassReader creader = new ClassReader(classBytes);
+		final ClassReader creader = new ClassReader(classBytes);
     	ClassWriter writer = new ClassWriter(ClassWriter.COMPUTE_MAXS);
     	RemappingClassAdapter visitor = new RemappingClassAdapter(writer,new Remapper(){
     		//rename a type reference
@@ -65,8 +65,8 @@ public String map(String typeName) {
     	}) {
     		//visit the body of the method
     		@Override
-    		public MethodVisitor visitMethod(int access, String name,
-    				String desc, String signature, String[] exceptions) {
+    		public MethodVisitor visitMethod(int access, final String name,
+    				final String desc, String signature, String[] exceptions) {
     			MethodVisitor mv = super.visitMethod(access, name, desc, signature, exceptions);
     			mv = new RemappingStringConstantAdapter(mv, new StringRemapper() {
     				//rename any string constants
@@ -75,7 +75,7 @@ public String remapStringConstant(String constant) {
     					//string constants will refer to the type using a dotted name; replace dots by slashes... 
     					String slashed = slashed(constant);
 						String to = fromTo.get(slashed);
-    	    			if(Hasher.containsGeneratedClassName(slashed) && to==null) {
+    	    			if(Hasher.containsGeneratedClassName(slashed) && to==null && !Hasher.isWhiteListConstant(creader.getClassName(), name, desc, slashed)) {
     	    				throw new NoHashedNameException(slashed);
     	    			}
     					if(to!=null) constant = dotted(to);
@@ -85,7 +85,7 @@ public String remapStringConstant(String constant) {
 				return mv;
     		}
     	};
-    	creader.accept(visitor, 0);
+    	creader.accept(visitor, ClassReader.EXPAND_FRAMES);
         return writer.toByteArray();
 	}
 }
diff --git a/Normalizer/src/de/bodden/tamiflex/normalizer/Hasher.java b/Normalizer/src/de/bodden/tamiflex/normalizer/Hasher.java
index 16eed49..d961568 100644
--- a/Normalizer/src/de/bodden/tamiflex/normalizer/Hasher.java
+++ b/Normalizer/src/de/bodden/tamiflex/normalizer/Hasher.java
@@ -39,7 +39,8 @@ public class Hasher {
 		"GeneratedSerializationConstructorAccessor",
 		"ByCGLIB",
 		"org/apache/derby/exe/",
-		"$Proxy" /*,
+		"_pyx",
+		"$Proxy" /*
 		"schemaorg_apache_xmlbeans/system/" these names seem to be stable, as they are already hashed */
 	};
 	
@@ -77,8 +78,8 @@ public void visitSource(String source, String debug) {
     		}
 
     		@Override
-    		public MethodVisitor visitMethod(int access, String name,
-    				String desc, String signature, String[] exceptions) {
+    		public MethodVisitor visitMethod(int access, final String name,
+    				final String desc, String signature, String[] exceptions) {
     			MethodVisitor mv = super.visitMethod(access, name, desc, signature, exceptions);
     			mv = new RemappingStringConstantAdapter(mv, new StringRemapper() {
     				@Override
@@ -86,8 +87,8 @@ public String remapStringConstant(String constant) {
     					String slashed = slashed(constant);
 		    			if(theClassName.equals(slashed)) return "$$$NORMALIZED$$$";
 						String to = generatedClassNameToHashedClassName.get(slashed);
-    	    			if(!theClassName.equals(slashed) && Hasher.containsGeneratedClassName(slashed) && to==null) {
-    	    				throw new NoHashedNameException(slashed);
+    	    			if(!theClassName.equals(slashed) && Hasher.containsGeneratedClassName(slashed) && to==null && !isWhiteListConstant(theClassName, name, desc, slashed)) {
+    	    				throw new NoHashedNameException("While visiting method: " + theClassName + "." + name + desc +": " + slashed);
     	    			}
     					if(to!=null) constant = dotted(to);
     					return super.remapStringConstant(constant);
@@ -96,7 +97,7 @@ public String remapStringConstant(String constant) {
 				return mv;
     		}
     	};
-    	creader.accept(visitor, 0);
+    	creader.accept(visitor, ClassReader.EXPAND_FRAMES);
         byte[] renamed = writer.toByteArray();
 		////////
 		String hash = SHAHash.SHA1(renamed);
@@ -134,7 +135,11 @@ public static String hashedClassNameForGeneratedClassName(String className) {
 	public static byte[] replaceGeneratedClassNamesByHashedNames(byte[] classBytes) {
 		return ClassRenamer.replaceClassNamesInBytes(generatedClassNameToHashedClassName,classBytes);		
 	}
-	
+
+	public static boolean isWhiteListConstant(String theClassName, String name, String desc, String slashed) {
+		return (slashed.equals("$Proxy") && theClassName.equals("java/lang/reflect/Proxy$ProxyClassFactory") && name.equals("apply"));
+	}
+
 
 	public static String dotted(String className) {
 		return className.replace('/', '.');