Latest WME version: WME 1.9.1 (January 1st, 2010) - download
var blockedDeskRegion = Scene.GetNode("block_desk"); blockedDeskRegion.Blocked = false;
Oops, thanks guys. It was a bug, the .Active attribute should work as well. I have just uploaded a fixed version of WME.
All is right again in the world WME Rocks!