Yes, that is called hair-pinning. ASA can be forced to allow hair-pinning, but it is disabled by default. I cannot remember the command to do this though.
The ability to allow hair-pinning is new in the 7.x series. There is no way allow it in 6.3.x on the pix. There aren't too many reasons to allow hair-pinning. If you think you need it, you should step back and take a hard look at the network design to make sure it is appropriate for your goals.
The basic thing to remember is the PIX/ASA is not a router. Yes, it has some basic routing functionality, but it won't behave entirely like a router.
