Ok, that usually means that although you **installed** java 1.3 or 1.4, you didn't **path** it. Instead, you're invoking the default java that came with Mandrake (or whatever distro you're using) which doesn't support -Xm* parameters. Run "java -version" or "which java" to verify this.

I'm using Mandrake and java v1.4, so I just added:

PATH=/usr/java/j2sdk1.4.0/jre/bin:$PATH

to my ~/.bash_profile file.

hth,
Pinhead