Xbee Pro 900HP - Model 002 (america) change AF or CM field in XCTU

Australian Model - XB9B-DMST-022
American Model - XB9B-DMST-002

American Frequency - 900 - 928Mhz
Australian Frequency - 915 - 927 Mhz

This link explains the frequencies. http://www.digi.com/support/kbase/kbaseresultdetl?id=3417

I saw a CM field in XCTU. Could I set the bit mask to block the frequencies not allowed in Australia?

use the SC (scan channels) value to do this:
http://www.digi.com/wiki/developer/index.php/Channels%2C_Zigbee

The SC command isn’t supported by the XBEE PRO 900Hp firmware.

For some of the other modules I’ve used (900 XSC, for example) there was a different firmware set available that enabled/disable the frequencies for the different regions.

Is there firmware available to support Australia or Singapore with these modules?

No, the Aus. government will not allow you to use a product that is not limited to the correct frequencies.