Diff q2438 and q2400

I have hardware with GSM module q2400.(evolution board)
I want remake my device for CDMA.
What is hardware (pin connector) different between q2400 and q2438?
What is default software settings for UART?
When I replace q2400 for q2438, I can’t receive answer for AT command. I have used different terminal program(hyper terminal, realterm) with different settings (9600 8 in 1 h/w control,9600 8 in 1 none control,115200 8 in 1 h/w control,115200 8 in 1 none control)

Best regards…