[R] Puzzling "Execution halted"

[Gang Chen]

I wrote an R program that does heavy computations with hundreds of
lines of code. It's running fine both interactively and in batch mode
on a Mac OS X computer. The program also has no problem running on a
Linux system (Fedora 14) interactively. However, when I try it on the
terminal in batch mode on the Linux system, it chokes in the middle of
the computation with the "Execution halted" error message.

I already put try or tryCatch in those places where computation may
throw an error. And the warnings are set in default (options(warn=1)).
I wish I could provide the code for help, but that seems impractical.
How to debug this?

Thanks,
Gang