Replaced Xbee PRO Through hole with Surface mount but doesn't work, why??

Ive been using XBee PRO’s for a while and would like to replace them on a new design with the Surface Mount type device. By just using the VCC, GND and ASSOC connected to a led, the led will flash to show that the radio is working. As soon as I replace the through hole part with a SMD type the led stays ON and of course the device does not seem to work, what gives. I have sent an email to customer support but will be waiting for a reply. I don’t want to spend money on a development board if I can avoid it as these parts should be just a drop in replacement.

What is the exact part number for each XBee in question and what firmware version are you running on each?

The Xbee PRO is the XBP24-AUI-001 ( S1 )
Current firmware version would be 10ED
Some have S1 some don’t but they all work with my equipment.
I am now trying to use the surface mount type
Not sure what the firmware version is as I have no means to connect it up to a computer unless I purchase a development board.
By connecting the vcc, gnd and associate, the led should flash as the other does when connecting new xbees to my product. These should be a direct drop in apart from different pin out, still no reply from digi. I may have to redesign the pcb to go back to the through hole device, pitty I was hoping to use the SMD type, cheers.

Figured it out, all good this end.