If you have analog lines you could set up a special ARS route to hit them then ring down to it.
Example.
5555 is an ARS route hits analog trunk group. Absorb ALL digits. This will leave you with CO dial tone.
Now use the associated directory number form to ring down to 5555.
Ralph
I don't know if this will work with PRIs or not. I'm sure it won't work with SIP.