With a fresh installation of ezpublish, choosing the ezwebin extension during setup, the wizard create the folder design/ezwebin_site. To override the standard favicon.ico file i tried to put a new one in design/ezwebin_site/images/favicon.ico, but this doesn't work (yes, I cleared the cache...). I tried to change the name of the folder from "ezwebin_site" to "ezwebin": in this case it works fine, if I put the favicon.ico file in design/ezwebin/images/, this override the default favicon.ico file.

Steps to reproduce

Install ezpublish with ezwebin extension
Put a new favicon.ico file in design/ezwebin_site/images/
Clear the cache
It doesn't work...
Rename design/ezwebin_site in design/ezwebin
Clear the cache
It works!