DTMF digits being skipped when dialing from Australia

Hi All,
I have set up an IVR system for my Australian client using Asterisk and Asterisk-Java FastAGI combination.
The system after receiving the call, prompts the user to enter his account number and then allows him to check his balance and do other things.
When the system receives calla from Australia, and prompts the user to enter his account number (followed by hash key), the system skips someof the digits entered by him. Say the client has entered 123456789#, the system reads it as 1245679# or something else. What I observwed is that someof the digits are being skipped.
This is working fine when I call the system from India.
Can anybody help me out of this as I cant figureout whats going wrong. Do I need to do some special configurations in Asterisk to read DTMF digits correctly??
Please help.

Can I please get some help ?? :cry:

Dear Friends,
This problem is really annoying me… can somebody sort this out?