Xilinx ISE 8.1i HDL simulation libraries compilation error

[samcheetah]

ive recently started using xilinx ISE 8.1i. its looks quite better than the previous version that i had. but when i compile the HDL libraries for simulation it gives me an internal error that there are too many files opened. i have 256MB of RAM and during the libraries compilation the page file usage goes upto 525MB.

my question is that is this error due to my low RAM or is it one of those ISE quirks.