BlueSmirf Uart Communication Trouble

So I’ve been having trouble interfacing the MSP430 LCD development board with the BlueSmirf. I have the BlueSmirf connected to a 4.5V source, and the MSP430 has a 3.3V source.

My problem is that when I try to send a command to the BlueSmirf, it doesn’t acknowledge it. However, I know that the transfer is working, because I’ve connected it to the receive port for the MSP430, and it receives fine. Also, when a cell phone connects to the BlueSmirf, the BlueSmirf sends an acknowledgement to the MSP430.

So my question is, does this sound like a Baud Rate problem (I currently have it set to a 9600 baud rate with the 1,048,576-Hz

SMCLK), or is it a voltage level problem? Is a 3.3V signal not large enough for the BlueSmirf to acknowledge?

Any help would be much appreciated.

Thanks!