wegrzyns,
Just in case you do decide to program the unit.
Go to:
Voice Services > OBiTALK Service >InboundCallRoute
Add this rule:
{(290xxxxxx)>(<**8:>(Mli)):li}
Where 290xxxxxx is your OBion number.
If your existing InboundCallRoute is ph then you need to end up with:
{(290xxxxxx)>(<**8:>(Mli)):li},{ph}