switching player models during game

[JEDI{Gunner}]

I tried switching player models in the game.....then the game stop i go back to my desktop and i see this in the dos window in the small box above all black window with all the sentences

 

Requested feature was omitted at compile time

 

I get this everytime i try to switch players.....can someone help me out,tell me what i am doing wrong or if i can even change player models