diff -r 2efb24cb8c36 -r a29adf86aa0c langtools/src/share/classes/com/sun/tools/javac/comp/Check.java
--- a/langtools/src/share/classes/com/sun/tools/javac/comp/Check.java	Fri Mar 25 15:17:52 2011 -0700
+++ b/langtools/src/share/classes/com/sun/tools/javac/comp/Check.java	Tue Mar 29 16:40:07 2011 +0100
@@ -676,7 +676,7 @@
                     "cant.apply.diamond.1",
                     t, diags.fragment("diamond.and.anon.class", t));
             return types.createErrorType(t);
-        } else if (!t.tsym.type.isParameterized()) {
+        } else if (t.tsym.type.getTypeArguments().isEmpty()) {
             log.error(tree.clazz.pos(),
                 "cant.apply.diamond.1",
                 t, diags.fragment("diamond.non.generic", t));