http://www.washingtonpost.com/wp-srv/aponline/20010924/aponline153515_000.htm

Why is Russia suddenly being so cooperative with the US led fight against Osama Bin Laden and international terrorism?

Here's why. It's a golden opportunity to tie Bin laden to Muslim rebels in Chechnya, have the latter labeled as terrorists, and completely defuse international criticism of Russia's human rights abuses in Chechyna.
I hate to sound cynical, but the Russians even floated the theory that Bin Laden might flee and seek refuge in Chechnya. That's a bit hard to swallow, but the Russians have done an excellent job portraying themseves as one of the 'good guys' in all of this.