Certain maps won't work.

I have this annoying error were some maps won’t work, i load them up fine but after about 5 maybe 10 seconds the game crashes and i get this error.

http://filesmelt.com/Imagehosting/pics/920cd38e30d5d5cb0cc09941add2ba7d.png

I’ve been getting this error for awhile now but i don’t know how to fix it.

I get that crash/error as soon as I move the mouse or take a step in cs_parkhouse or cs_militia

I get the same in cs_militia.