Bilal,
If I understand the question correctly, you wish the OBi110 to send out from the Line Port:
0 > pause for pbx dial tone > 09122102949
This can be done, but more information is needed.
1. What is the range of numbers this should apply to?
2. Do any other services on the OBi110 use the same range of numbers?
3. What is your Phone Port PrimaryLine? (Default is PSTN).