--- old/src/java.desktop/unix/classes/sun/awt/X11/XClipboard.java	2014-12-11 14:18:17.743455673 +0300
+++ new/src/java.desktop/unix/classes/sun/awt/X11/XClipboard.java	2014-12-11 14:18:17.655455670 +0300
@@ -281,6 +281,11 @@
             }
         }
 
-        checkChange(formats);
+        XToolkit.awtUnlock();
+        try {
+            checkChange(formats);
+        } finally {
+            XToolkit.awtLock();
+        }
     }
 }