anyone? 2008/12/22 sol sol

hi, in the customer interface there is the field ówner´ for the ticket. Standard it show the username of the owner, (f.e . : abbbbb) where can i find the settings to change this to the first and/or last name of the owner? (f.e. aaa bbbb)

I really cant find it , and it would be stupid to change all the agent user id´s..

thanks!