$User-ID link to bbpress ?!?

Hey.

I (succesfully) integrated bbpress and WP and BBP share the user database. I use a WP-Plugin called “MyAccount” which gives the user a few options on what to do (profile, logout,…)
I do not want the user to use his wordpress profile, but only the bbpress profile so I try to change the “profile” link WordPress to:

http://myurl.com/forum/profile/$User-ID

The username is the same for both WP and BB, but unfortunately the link now actually goes to http://myurl.com/forum/profile/$User-ID instead of actually replacing the $User-ID with the username.

Could anybody help me out and let me know how I can make it happen that $User-ID is replaced by the actual userame?

Thanks in advance!!