The pre-compiled version(s) of VMware Tools does not work with Ubuntu running a kernel newer than 2.6.15-27-386. Note that this problem persists in VMware Workstation 5.5.4.

The quick and dirty solution to this problem is use GRUB to select the "old" kernel. This process is shown in the "Menu Configuration" section of "Boot with GRUB" by Wayne Marshall here:

http://www.linuxjournal.com/article/4622

The other option involves compiling your own version of VMware Tools.