I would suggest you to download the latest version of MPLAB (V8.0x) and see if it works better.

In your Program, you Should change
Code:
 INT_Handler RBC_INT, _EncChg, ASM, yes
to
Code:
 INT_Handler RBC_INT, _EncChg, PBP, yes
unless it might not behave the way you want. You also must include the REEnter.bas file.