Advanced Calling Broken

I have many contacts with phone numbers that include commas (a comma makes the dialer wait one second), some of which are meant for entry of calling card account numbers while calling overseas, etc. When I turn on Advanced Calling, for every phone number which has a comma, the first comma and everything after it are ignored by the dialer. Someone suggested I use a "p" instead of the comma, but it turns out the phone does not allow me to enter a "p" in the phone number field for a contact.

This makes Advanced calling useless for me. Does anyone have any ideas on how to resolve this issue?