RE_EndFrame

hello guys i'm currently hooking endframe using an VEH hook (using zhap's method) now it works perfectly in mw2 but cod7 it will crash now and again

here is the addresses im using:

DWORD dwEndFrameException = 0x5063CE;
DWORD dwEndFrameContinue = 0x5063E7;
DWORD CG_DrawSnapShotTime = 0xC9D0CC;

RE_EndFrame
void __thiscall sub_506360(void *this, int a2)

now i'm just wondering if anyone else has had a problem using this function

and btw detouring works fine but this way just fails any help or tips will be helpful

in black ops they scan for exception handlers, the only way around it is
using their handler or hooking the scan