Ubuntu 12.04 + VMware Tools = some Warnings + Errors
http://shaurong.blogspot.com/2012/05/ubuntu-1204-desktop-x86-vmware-tools.html
Looks like you did install VMware Tools successfully and ran vmware-toobox. I'm not sure what your problem is
The 8.0.3 release notes claim that Ubuntu 12.04 is supported as a guest:
This release of VMware Workstation supports Ubuntu 12.04 as a guest operating system.
However, it looks like tools installation still fails to build the vmxnet module, as the op's linked page shows.
When is this going to be fixed?