Alright, I have the solution to those who want to play mp without the game cd. As stated in some of the posts, if you use a no-cd patch, the mp wont work, so instead of patching the jk2mp.exe, use a loader instead.
First of all, make sure you have a non-patched mp.exe like off the game cd.
Then goto gamecopyworld.com and download the "Jedi Knight 2 v1.0 SP/MP [ENGLISH] No-CD #2" file. This zip has a mp loader that you put in your gamedata dir and execute that starts the jk2mp.exe without actually modifying the file, and there you have it, mp games without cd and without damn errors! Enjoy!