org.geoserver.catalog.impl.ProxyList is said to be immutable, but it's not

--- a/src/main/src/main/java/org/geoserver/catalog/impl/ProxyList.java
+++ b/src/main/src/main/java/org/geoserver/catalog/impl/ProxyList.java
@@ -4,7 +4,6 @@
  */
 package org.geoserver.catalog.impl;
 
-import java.lang.reflect.Proxy;
 import java.util.AbstractList;
 import java.util.List;
 
@@ -35,12 +34,8 @@ public abstract class ProxyList extends AbstractList {
     
     @Override
     public Object set(int index, Object element) {
-        if ( !proxyInterface.isInstance( element ) || !(element instanceof Proxy) ) {
             throw new IllegalArgumentException( 
                 "Object is not a proxy, or not a proxy of the correct type");
-        }
-        
-        return proxyList.set(index, unwrapProxy(element, proxyInterface));
     }
     
     public int size() {
diff --git a/src/main/src/test/java/org/geoserver/catalog/impl/CatalogImplTest.java b/src/main/src/test/java/org/geoserver/catalog/impl/CatalogImplTest.java
index 6bee7b8..7a2410a 100644
--- a/src/main/src/test/java/org/geoserver/catalog/impl/CatalogImplTest.java
+++ b/src/main/src/test/java/org/geoserver/catalog/impl/CatalogImplTest.java
@@ -1386,16 +1386,22 @@ public class CatalogImplTest extends TestCase {
         List<StyleInfo> styles = catalog.getStyles();
         assertEquals( 2 , styles.size() );
         
-        assertEquals( s.getName(), styles.get( 0 ).getName() );
-        assertEquals( "a"+s.getName(), styles.get( 1).getName() );
-        
-        //test sorting
-        Collections.sort( styles, new Comparator<StyleInfo>() {
+        //test immutability
+        Comparator<StyleInfo> comparator = new Comparator<StyleInfo>() {
 
             public int compare(StyleInfo o1, StyleInfo o2) {
                 return o1.getName().compareTo( o2.getName());
             }
-        });
+        };
+        try {
+            Collections.sort(styles, comparator);
+            fail("Expected runtime exception, immutable collection");
+        } catch (RuntimeException e) {
+            assertTrue(true);
+        }
+
+        styles = new ArrayList<StyleInfo>(styles);
+        Collections.sort(styles, comparator);
         
         assertEquals( "a"+s.getName(), styles.get( 0 ).getName() );
         assertEquals( s.getName(), styles.get( 1 ).getName() );