Answer to the first question:
Yes MPLAB-SIM (not MPASM) can simulate interrupts, like change on pin,
Timer, WDT.

Answer to the second:
No MPLAB-SIM does not support RS-232 interrupts.
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___________________________
|     Darrel Johansen     |
|     tempe,  arizona     |
|   darrelj@primenet.com  |
|_________________________|