> pic chips have only one interrupt vector
Yes and no. 18F-series chips have two, one high priority (0x0008h) and one low pritority (0x0018h) and the DEFINE's, as they were written in ONE of the code examples posted was defining one handler for the high priority and one for the low. However, both handlers had RETFIE FAST at the end which, to me, seems like a mistake if there's any possibillity of a high priroty interrupt tripping while a low priority interrupt is executing. It may be why they worked on their own but not both at the same time.

Anyway, if you got it working then none of it really matters.

/Henrik.