on the new vmware ESX if you right click on guest OS virtual maching then select install vmware tools this mounts the cd then type in the following commands:
sudo apt-get install build-essential linux-headers-`uname -r`
mount /media/cdrom
cp /media/cdrom/VMwareTools-*.tar.gz /tmp/ && cd /tmp/ && tar xf VMwareTools-*.tar.gz && cd vmware-tools-distrib/
sudo ./vmware-install.pl