backend failing (authentication required)

[Sam Anderson]

i am having a problem that recently came up kind of out of the blue.
after working fine for 8 months or so i started getting the following message in my log files after the print job had been sent:

these are the last relevant lines in the log:
D [19/Jan/2007:08:36:37 -0600] [Job 289] Copying page 61...
D [19/Jan/2007:08:36:37 -0600] [Job 289] pagew = 570.0, pagel = 817.0
D [19/Jan/2007:08:36:37 -0600] [Job 289] bboxw = 595, bboxl = 842
D [19/Jan/2007:08:36:37 -0600] [Job 289] PageLeft = 12.5, PageRight = 582.5
D [19/Jan/2007:08:36:37 -0600] [Job 289] PageTop = 829.5, PageBottom = 12.5
D [19/Jan/2007:08:36:37 -0600] [Job 289] PageWidth = 595.0, PageLength = 842.0
D [19/Jan/2007:08:36:37 -0600] [Job 289] Copying page 62...
D [19/Jan/2007:08:36:37 -0600] [Job 289] pagew = 570.0, pagel = 817.0
D [19/Jan/2007:08:36:37 -0600] [Job 289] bboxw = 595, bboxl = 842
D [19/Jan/2007:08:36:37 -0600] [Job 289] PageLeft = 12.5, PageRight = 582.5
D [19/Jan/2007:08:36:37 -0600] [Job 289] PageTop = 829.5, PageBottom = 12.5
D [19/Jan/2007:08:36:37 -0600] [Job 289] PageWidth = 595.0, PageLength = 842.0
D [19/Jan/2007:08:36:38 -0600] [Job 289] Wrote 62 pages...
D [19/Jan/2007:08:36:38 -0600] PID 7576 (/usr/libexec/cups/filter/pstops) exited with no errors.
D [19/Jan/2007:08:36:39 -0600] PID 7577 (/usr/libexec/cups/filter/rastertosamsungspl) exited with no errors.
D [19/Jan/2007:08:36:39 -0600] [Job 289] File 0 is complete.
I [19/Jan/2007:08:36:39 -0600] [Job 289] Backend returned status 2 (authentication required)
D [19/Jan/2007:08:36:39 -0600] Discarding unused printer-state-changed event...
D [19/Jan/2007:08:36:39 -0600] Discarding unused job-stopped event...
D [19/Jan/2007:08:41:01 -0600] Closing client 7 after 300 seconds of inactivity...
D [19/Jan/2007:08:41:01 -0600] cupsdCloseClient: 7

it's the authentication required line that is the only thing i would know to go from, but googling and searching the forums didn't turn up anything, so i would appreciate any help you could give.

thanks!
-Sam Anderson