fix compilation for sun jdk

git-svn-id: https://svn.apache.org/repos/asf/wicket/branches/wicket-1.5-M1@983292 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/wicket/src/main/java/org/apache/wicket/util/tester/FormTester.java b/wicket/src/main/java/org/apache/wicket/util/tester/FormTester.java
index 85ff185..1db1038 100644
--- a/wicket/src/main/java/org/apache/wicket/util/tester/FormTester.java
+++ b/wicket/src/main/java/org/apache/wicket/util/tester/FormTester.java
@@ -377,8 +377,9 @@
 		{
 			@SuppressWarnings("unchecked")
 			@Override
-			public void onFormComponent(final FormComponent formComponent, IVisit<Void> visit)
+			public void onFormComponent(FormComponent<?> formComponent2, IVisit<Void> visit)
 			{
+				final FormComponent formComponent=formComponent2;
 				// do nothing for invisible component
 				if (!formComponent.isVisibleInHierarchy())
 				{