301 redirect user profiles from username to userid

Hello,
Due to lot of improper registrations been done on our forums using variety of languages and special characters we have changed our member profile urls from following

www.mydomain.com/members/userNAME.php
to
www.mydomain.com/members/userID.php

Now, it was very dissappointing to find a huge 404 not found pages generated in WebMaster Tools.
All the username.php profiles were not 301 or 301 (whichever is better) re-directed.

Can you please give us a fix for same ?

I am using vbseo 3.2

Thank You.

Related: Using userid vs username + small question

The solution I posted would probably work only if theres no user with a 'username' of u[some number]
like... u1234. Otherwise, that user's profile URL redirection would become an infinite loop.

We have several active users with those usernames
like u1, u0234, uu234234, username, user1 etc.

Do we have a fix for this problem ?