Optimize RSL - File too large

I am trying to optimize my RSL-files size using the optimizer-tool inside Flex SDK, following this guide:
http://livedocs.adobe.com/flex/3/html/help.html?content=rsl_07.html

I first tried with a small RSL *(1kb) *and it worked perfectly, however!
When I tried it on my real RSL-file, I get an error message from Java saying that it’s out of memory.
I have changed the maximum heap size for Java, I managed to get it up to **1566mb **maximum
and it’s still running out of memory!

1566mb is maximum on the 32-bits java it seems, and Flex doesn’t support 64-bits java.

I really want to keep the RSL in just one file! *(If I split it up in two, it should work)
*Thanks in advance,
Tompa