oes on esx server

Does anyone have experience installing OES on VMWare ESX Server v2.5.1? I can't seem to get vmware tools to work. And my network device doesn't work, but I'm assuming this will be taken care of by getting vmware tools to work. When I run the vmware tools install, I get this:

None ov VMware Tools's pre-built vmmemctl modules is suitable for your running kernel. Do you want this program to try to build the vmmemctl module for your system?

When I choose yes, it says:

Setup is unable to find the gcc program on your machine. Please make sure it is installed.

Thanks in advance for the help.
Mike