I haven't been able to make pac/auto-conf files work in mozilla on either Mac OS-X or Linux 7.2 w/ recent Mozilla builds (0.9.7 on Mac, 0.9.6 on Linux).
Searching the archives didn's turn up anything.. but I could have chosen the wrong search key words :) Is this a known problem? Any way to fix? Workaround? Its really a bummer to keep changing the damn proxy settings when a well designed pac file solves lots of problems!! Owen