New Patch for vSphere

Things got a bit weird a couple of weeks ago while trying to upgrade my home lab from 4.1 to 5.1.

The install of SSO went fine but upgrading the Inventory Service threw up the following error:
Error 29102 . Could not contact Lookup Service. Please check VM_ssoreg.log in system temporary folder for details.

So I dutifully checked the required log file and googled it. It turns out that if the FQDN has the word “port” in it anywhere the install/uprade will fail. REALLY?!?? 
It turns out that this is fixed in 5.1.0a (Build 880471). you can find the details here.
Upgrading to 5.1.0a worked. How that bug got in there is mind boggling.