maybe you could:
1) put the new RAM at a different
address range and do a test
compilation (and maybe a debug
run on a simulator). you
could move it back to the address
range starting with 0000, before
doing your normal compile/debug.
2) if you can dump simulated
xdata to a file, you could check
for writes to addresses outside
your specified address ranges.
but not reads, i guess. unless
you can set breakpoints on reads
of address ranges, with your simulator.

james