PRESENT WAR is a cool mod for MoH: Allied Assault that turns the game into a "modern experience ". Every single weapon is changed for a new model (now you have H&K MP5, AK-47, DRAGUNOV, M4A1, etc....), and also most of the enemies are replaced with new models (Counter-Strike terrorists, islamic terrorists, and saddam hussein ).
The mod covers both: Single Player and Multi Player.
Get it here:
http://medalofhonor.filefront.com/file/Present_War_Weapons;21406
Enjoy it