I found that Firefox 3.6 does not work with VMware Server 2.0.2.
You cannot access the VM consoles - it seems that the required vmware plugin does not fit later firefox versions.

So how to run an older version of firefox?

Here is what I did:
Get a legacy firefox from ftp://ftp.mozilla.org/pub/mozilla.org/firefox/releases/
(I chose version 3.0.6)

'cd ~'
'wget ftp://ftp.mozilla.org/pub/mozilla.org/firefox/releases/3.0.6/linux-i686/en-GB/firefox-3.0.6.tar.bz2'
'tar xvfj firefox-3.0.6.tar.bz2'
'cd firefox'


The binary 'firefox-bin' has been linked against some of the local .so libs in the firefox tarball.
Your system will need to know the locations of these libs before firefox can run:
"./firefox-bin: error while loading shared libraries: libjemalloc.so: cannot open shared object file: No such file or directory"

Use ldd to probe the binary for unknown libs:

$ ldd firefox-bin | grep found
	libjemalloc.so => not found
	libxul.so => not found
	libmozjs.so => not found
	libxpcom.so => not found

So I copied them over to /usr/local/lib, added the location to ld.so.conf and re-ran ldconfig:
( I kept the version string in case I want to run other versions later.. )

'mkdir /usr/local/lib/firefox-3.0.6'
'cp libjemalloc.so /usr/local/lib/firefox-3.0.6'
'cp libxul.so /usr/local/lib/firefox-3.0.6'
'cp libmozjs.so /usr/local/lib/firefox-3.0.6'
'cp libxpcom.so /usr/local/lib/firefox-3.0.6'

'echo "/usr/local/lib/firefox-3.0.6" > /etc/ld.so.conf.d/firefox-3.0.6.conf'   # I'm on Linux Mint, your ld.so.conf setup may vary.
'ldconfig'


Now firefox should work:
'~/firefox/firefox'

I also found that the vm console would crash unless I added 'mainMem.useNamedFile = "FALSE"' to the VMs .vmx config file.
This might be due to running the VMs from an NFS volume but ymmv.