For integration reasons I need to make this change but I don't know how.

I am running UBB Version 6.1.0.2

Currently, to view Member #2's recent posts on my site, the URL is:
http://www.jexeca.com/cgi-bin/ubb-cgi/ultimatebb.cgi?ubb=recent_user_posts&u=00000002

But I want it to be:
http://www.jexeca.com/cgi-bin/ubb-cgi/ultimatebb.cgi?ubb=recent_user_posts&u=generalm10

(Member #2's LOGIN name is generalm10)

How can I accomplish this?? Thanks!