Some others have had similar issues and the below seems to work for
them.
http://communities.vmware.com/thread/47087;jsessionid=39457F4E8F56574B66
76CBCB61D3BD30?tstart=0&start=25
1. go to the license server
2. in the license server app i click "Reload license
file" and stop/start the service
3. go into VC2 and select the ESX server
4. pull off the license so the server is
"unlicensed"
5. put the license back on