Your question has nothing to do with Apple Remote Desktop..the focus of this forum, and Apple's application for managing Macs on a network. Please post your question on Microsoft's own forums for their Mac software: http://answers.microsoft.com/en-us/mac
This link was referenced as the fix from the Microsoft forum
I can confirm that the first link carries the solution. Search for string "RESOLVED!" on the page and grab the v2.1.2 RDC that was leaked. It solved the problem for me, which had been driving me absolutely bonkers after licencing a 2008 R2 server with TS CALs.