/etc/vmware/init.d/vmware uses insmod to load vmmon and vmnet. If the sysadmin has put vmmon or vmnet in /etc/modules.autoload.d/kernel-2.x, then vmware will fail to start. If the script is changed to use modprobe instead, this problem goes away. The ebuild should either have a fix for this script or perhaps a warning that says "don't put vmmon and/or vmnet in your autoload list".
This has been fixed for a little while, I just forgot to mention it in the bug.