Hi,
As far as I can see the RTC can be clocked either by the TMR1 Oscillator using a 32.768kHz crystal OR from the internal low power RC-oscillator. I don't think there's a way to drive the RTC module from the "normal" internal oscillator because then the RTC would shut down when the PIC enters low power mode since the oscillator is shut down. And, in the datasheet, below table 31-16 it says: The Timer1 oscillator is designed to drive 32.768 kHz crystals. When T1CKI is used as a digital input, frequencies up to 12 MHz are supported. So I don't think reworking a board to replace the 32kHz crsytal with something else is going to work either....

The only thing *I* can currently come up with is the include some test-code in the firmware that basically advances the clock by 59 min 58 seconds after each "1-hour task" and so on. Obviously, doing so may introduce OTHER bugs but what you're going to do?

/Henrik.