BlueSmirf w/o USB-to-Serial Adapter b.w. Arduino


is it possible to configure a Sparkfun BlueSmirf Bluetooth module without using a Sparkfun USB-2-Serial Adapter?

I've connected BlueSmirf's Tx to Arduino Rx and BlueSmirf's Rx to Arduino Tx. If, however, I'm issueing an AT command via a terminal emulation, I'm not getting any response.

Does anybody have an idea? Any suggestions are highly appreciated.