Am I hitting a 3GB memory (user space) limit?

Hi,

I'm trying to remaster Knoppix 3.4 to a DVD. I'm using the official distro to do my remaster and am running into problems. I'm not acutually customizing anything, but have added a 4GB .tar file. The create_compressed_fs command always seems to crash on me. After trying (what seems like an infinite number of) different things I started to notice that my crash was always occuring when the VmSize of the create_compressed_fs process reached about 3GB. After a little more research I'm getting the impression that there is a 3GB limitation on user space memory. Is this possible? If so, is there a way for me to work around it.

Any help would be appreciated,
Ryan