Yeh, I thought of using two mono sources, but I was wondering if it could be done with a single source. Guess it isn't possible, according to that quote. Seems odd that OpenAL doesn't have this ability. Even the buggy old Javasound library allows panning.
My experience with OpenAL's built-in 3D panning of mono sources, is that it doesn't work very well. I can only hear the panning when the source is really close to the listener, like distance <= 1. Further distances do not seem to pan, regardless of their position in relation to the listener. I don't know if it is just my soundcard, or what. You wouldn't happen to have any experience with this, would you? I'm thinking maybe there are some AL settings I have to change or something to get OpenAL's built-in panning to work for far-away mono sources.