2.5.3 3D Window doesnt zoom rotate, or scale

Has this happened to anyone else? For me, the 2.5.3 3D windows don’t seem to respond to the Alt, Ctrl-Alt, Shift Alt buttons and the header won’t slide back and forth with the Alt Key. I double checked it running 2.5.2 on the same computer and these functions worked fine. Has anyone else run into this problem?

In the User Preferences / Input tab, select Emulate 3 Button Mouse