i think i have the same problem. do you need to run a configure command on java_vm, or something? (i'm new to linux, if you haven't figured that out already!)
more details:
i also sent a form to java tech support because i downloaded j2re-1_4_0_01-linux-i586.rpm.bin, but running "./" produced the file j2re-1_4_0_01-fcs-linux-i386.rpm, contrary to the installation guide at:
http://java.sun.com/j2se/1.4/jre/install-linux.html
i don't know if that is the right file. sun sent me an email saying they're looking into it and implied they have to ask download.com to check the file.
i ran rpm on the file and it seemed to install the 1.4.0.01 version of java. but running "sh ./LimeWireLinux.bin" said i didn't have java vm installed. i added "/usr/java/bin" to my path (and yes, java_vm is in fact there) but i got the same response from LimeWire.
p.s. i'm running mandrake 8.2, if it matters.