I never had this problem in our 5.1 environment which we upgraded from 4.1, but in a new freshly installed 5.1U1 environment I am having this problem. It seems to be a known issue with no solution which is pretty frustrating. It doesn't seem to be every host profile I use though which is strange. I will be opening a support ticket to make them aware that this is still an issue.
kb.vmware.com/kb/2032817