Have been using Audacity 1.3.10-beta-unicode, on Debian Testing 64, and 
I must say, major congrats.  I am using it with the Jack driver, since I 
keep Jack on all the time; very very good!!!

J.E.B.
    
You got it (and Portaudio) to work with Jack? I had to use weird
workarounds involving an external USB card to do that...

  
Apparently so :-)  I have ALSA, Jack, and Pulse working together (in this structure).  For some reason the Pulse driver didn't work, but the Jack driver is working delightfully.

J.E.B.