From what I've been able to find, the Ooma supports 7-, 10-, and 11-digit US dialing as well as 011 + country code + number for international calling. If that's correct, you might try the following:
Physical Interfaces -> PHONE Port -> PrimaryLine : PSTN Line
Physical Interfaces -> LINE Port -> DigitMap:
(xxxxxxxS4|<1>[2-9]xxxxxxxxxS0|1xxxxxxxxxxS0|011xx.|xx.|<**9ob>xxxxxxxxxS4)
Dialing 7-, 10-, or 11-digit numbers or 011 + country code + number should go out the LINE Port to the Ooma.
Dialing 9-digit numbers should go out the OBiTALK Port.
If you have providers on SP1 and/or SP2, **1 + number and/or **2 + number should go out those ports.