Forums site redirecting

I am using IE9 9.0.8112.16421 updated to KB2719177.  I have this address:

    http://social.msdn.microsoft.com/Forums/en-US/vblanguage

set as a shortcut and it works just fine.   But other references to that page (for instance, from a thread within that page) are all to

    http://social.msdn.microsoft.com/Forums/en-US/vblanguage/Threads

and that link always takes me to

    http://msdn.microsoft.com/en-US/

All my shortcuts to the groups are set up without the /Threads.  But this is the only one that behaves differently between the two addresses.

What sorts of things could cause the second form of the address to be redirected like that?