JSF is able to integrate with GWT. With Wicket I'm not sure.
Investigate the JSF's ExternalContext purposed for integration with other app contexts. By bridging state (re-writing) and through URL-rewriting you might succeed.
My 2-cents would be JSF + GWT, Although, Wicket is a powerful piece of equipment.
It's an intriguing thought mixing them all. Seam Solder (and possibly Seam Servlet) should be helpful in such sense.