I wouldn't recommend doing this, even if you could (running the same wallet in both Bitcoin-Qt and another application at the same time), but there is so much demand, I will be making it possible with the new wallets coming up... soon?  Hopefully soon...

Therefore, even when you can import them, unless you switch over to Armory completely, I recommend you just create a new Armory wallet and send funds to it.  Especially because Armory wallets can be backed up with four-lines of data -- your Satoshi wallet will require one line of information for each address, and then you'll additionally have to backup the Armory wallet, anyway.