I've submitted a new feature request for adding wicket support to seam-gen.
I've also submitted a patch which provides rudimentary support for this.
Currently the functionality is limited to:
1. seam setup asks whether to use wicket OR jsf and subsequently asks for a wicket package.
2. seam create-project will, if wicket is selected during setup, generate enough structure and code to build and run the most minimal of seam&wicket application, as per http://in.relation.to/Bloggers/SeamlessWicket
3. I've not produced idea support, but eclipse works, netbeans should too.
If there are any wicket&seam users who would like to test this then please feel do so.
Please provide feedback - and any other comments which would help this work be adopted into the mainline repository.