I confirm that my 1350W is still not working. Printer is detected. Manually printing to /dev/lp0 works. Just cups doesn't work. Details attached.

dmesg shows:
[4618112.412000] usb 5-8.3: new full speed USB device using ehci_hcd and address 7
[4618112.503000] drivers/usb/class/usblp.c: usblp0: USB Bidirectional printer dev 7 if 0 alt 0 proto 2 vid 0x0686 pid 0x300B

These commands print a postscript file w/o problem.
cat PS_FILE | gs -q -dNOPAUSE -dPARANOIDSAFER -dBATCH -sDEVICE=pbmraw -dDEVICEWIDTHPOINTS=595 -dDEVICEHEIGHTPOINTS=842 -r600 -sOutputFile=- - | min12xxw -m 1350W -f a4 -r 600 | sudo dd of=/dev/usblp0

I use gnome-cups-manager to "Print Test Page". This is shown in the logs:
D [28/May/2006:15:37:02 +0800] [Job 7] argv[0]="PagePro-1350W"
D [28/May/2006:15:37:02 +0800] [Job 7] argv[1]="7"
D [28/May/2006:15:37:02 +0800] [Job 7] argv[2]="sltam"
D [28/May/2006:15:37:02 +0800] [Job 7] argv[3]="Test Page"
D [28/May/2006:15:37:02 +0800] [Job 7] argv[4]="1"
D [28/May/2006:15:37:02 +0800] [Job 7] argv[5]="job-uuid=urn:uuid:8e273b75-64a3-366c-785d-6ccc64536ff8"
D [28/May/2006:15:37:02 +0800] [Job 7] argv[6]="/var/spool/cups/d00007-001"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[0]="CUPS_CACHEDIR=/var/cache/cups"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[1]="CUPS_DATADIR=/usr/share/cups"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[2]="CUPS_DOCROOT=/usr/share/cups/doc-root"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[3]="CUPS_FONTPATH=/usr/share/cups/fonts"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[4]="CUPS_REQUESTROOT=/var/spool/cups"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[5]="CUPS_SERVERBIN=/usr/lib/cups"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[6]="CUPS_SERVERROOT=/etc/cups"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[7]="CUPS_STATEDIR=/var/run/cups"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[8]="PATH=/usr/lib/cups/filter:/usr/bin:/usr/sbin:/bin:/usr/bin"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[9]="<email address hidden>"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[10]="SOFTWARE=CUPS/1.2.0"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[11]="TMPDIR=/var/spool/cups/tmp"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[12]="TZ=Asia/Hong_Kong"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[13]="USER=root"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[14]="CUPS_SERVER=/var/run/cups/cups.sock"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[15]="CUPS_ENCRYPTION=IfRequested"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[16]="IPP_PORT=631"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[17]="CHARSET=utf-8"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[18]="LANG=en_US"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[19]="PPD=/etc/cups/ppd/PagePro-1350W.ppd"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[20]="RIP_MAX_CACHE=8m"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[21]="CONTENT_TYPE=application/postscript"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[22]="DEVICE_URI=usb://KONICA%20MINOLTA/PP1350W"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[23]="PRINTER=PagePro-1350W"
D [28/May/2006:15:37:02 +0800] [Job 7] envp[24]="FINAL_CONTENT_TYPE=printer/PagePro-1350W"
I [28/May/2006:15:37:02 +0800] Started filter /usr/lib/cups/filter/pstops (PID 15301) for job 7.
I [28/May/2006:15:37:02 +0800] Started filter /usr/lib/cups/filter/foomatic-rip (PID 15302) for job 7.
I [28/May/2006:15:37:02 +0800] Started backend /usr/lib/cups/backend/usb (PID 15303) for job 7.
D [28/May/2006:15:37:02 +0800] Discarding unused job-state event...
D [28/May/2006:15:37:02 +0800] cupsdProcessIPPRequest: 7 status_code=0 (successful-ok)
D [28/May/2006:15:37:02 +0800] [Job 7] Page = 595x842; 12,12 to 583,830
D [28/May/2006:15:37:02 +0800] [Job 7] slow_collate=0, slow_duplex=0, slow_order=0
D [28/May/2006:15:37:02 +0800] [Job 7] Before copy_comments - %!PS-Adobe-3.0
D [28/May/2006:15:37:02 +0800] [Job 7] %!PS-Adobe-3.0
D [28/May/2006:15:37:02 +0800] [Job 7] %%Title: PPR Test Page
D [28/May/2006:15:37:02 +0800] [Job 7] %%Pages: 1
D [28/May/2006:15:37:02 +0800] [Job 7] %%DocumentNeededResources: font Helvetica
D [28/May/2006:15:37:02 +0800] [Job 7] %%EndComments
E [28/May/2006:15:37:02 +0800] [Job 7] No %%BoundingBox: comment in header!
D [28/May/2006:15:37:02 +0800] [Job 7] Before copy_prolog - %%BeginProlog
D [28/May/2006:15:37:02 +0800] [Job 7] Before copy_setup - %%BeginSetup
D [28/May/2006:15:37:02 +0800] [Job 7] Before page loop - %%Page: 1 1
D [28/May/2006:15:37:02 +0800] [Job 7] Copying page 1...
D [28/May/2006:15:37:02 +0800] [Job 7] pagew = 570.5, pagel = 817.5
D [28/May/2006:15:37:02 +0800] [Job 7] bboxw = 595, bboxl = 842
D [28/May/2006:15:37:02 +0800] [Job 7] PageLeft = 12.2, PageRight = 582.8
D [28/May/2006:15:37:02 +0800] [Job 7] PageTop = 829.8, PageBottom = 12.2
D [28/May/2006:15:37:02 +0800] [Job 7] PageWidth = 595.0, PageLength = 842.0
D [28/May/2006:15:37:02 +0800] [Job 7] perl: warning: Setting locale failed.
D [28/May/2006:15:37:02 +0800] [Job 7] perl: warning: Please check that your locale settings:
D [28/May/2006:15:37:02 +0800] [Job 7] LANGUAGE = (unset),
D [28/May/2006:15:37:02 +0800] [Job 7] LC_ALL = (unset),
D [28/May/2006:15:37:02 +0800] [Job 7] LANG = "en_US"
D [28/May/2006:15:37:02 +0800] [Job 7] are supported and installed on your system.
D [28/May/2006:15:37:02 +0800] [Job 7] perl: warning: Falling back to the standard locale ("C").
D [28/May/2006:15:37:02 +0800] [Job 7] Printer using device file "/dev/usblp0"...
D [28/May/2006:15:37:02 +0800] [Job 7] LPGETSTATUS returned a port status of 08...
W [28/May/2006:15:37:02 +0800] [Job 7] Printer off-line.
D [28/May/2006:15:37:02 +0800] [Job 7] foomatic-rip version $Revision: 3.43.2.15 $ running...
D [28/May/2006:15:37:02 +0800] [Job 7] Parsing PPD file ...
D [28/May/2006:15:37:02 +0800] [Job 7] *cupsFilter: "application/vnd.cups-postscript 0 foomatic-rip"
D [28/May/2006:15:37:02 +0800] [Job 7] Added option ColorSpace
D [28/May/2006:15:37:02 +0800] [Job 7] Added option PageSize
D [28/May/2006:15:37:02 +0800] [Job 7] Added option PageRegion
D [28/May/2006:15:37:02 +0800] [Job 7] Added option ImageableArea
D [28/May/2006:15:37:02 +0800] [Job 7] Added option PaperDimension
D [28/May/2006:15:37:02 +0800] [Job 7] Added option InputSlot
D [28/May/2006:15:37:02 +0800] [Job 7] Added option MediaType
D [28/May/2006:15:37:02 +0800] [Job 7] Added option Resolution
D [28/May/2006:15:37:02 +0800] [Job 7] Added option Economode
D [28/May/2006:15:37:02 +0800] [Job 7] Added option Model
D [28/May/2006:15:37:02 +0800] [Job 7] Added option DriverPageSize
D [28/May/2006:15:37:02 +0800] [Job 7] Added option GSPageSize
D [28/May/2006:15:37:02 +0800] [Job 7] Added option GSResolution
D [28/May/2006:15:37:02 +0800] [Job 7] Added option DriverResolution
D [28/May/2006:15:37:02 +0800] [Job 7] Added option Font
D [28/May/2006:15:37:02 +0800] [Job 7]
D [28/May/2006:15:37:02 +0800] [Job 7] Parameter Summary
D [28/May/2006:15:37:02 +0800] [Job 7] -----------------
D [28/May/2006:15:37:02 +0800] [Job 7]
D [28/May/2006:15:37:02 +0800] [Job 7] Spooler: cups
D [28/May/2006:15:37:02 +0800] [Job 7] Printer: PagePro-1350W
D [28/May/2006:15:37:02 +0800] [Job 7] PPD file: /etc/cups/ppd/PagePro-1350W.ppd
D [28/May/2006:15:37:02 +0800] [Job 7] Printer model: Minolta PagePro 1350W Foomatic/min12xxw (recommended)
D [28/May/2006:15:37:02 +0800] [Job 7] Job title: Test Page
D [28/May/2006:15:37:02 +0800] [Job 7] File(s) to be printed:
D [28/May/2006:15:37:02 +0800] [Job 7] <STDIN>
D [28/May/2006:15:37:02 +0800] [Job 7]
D [28/May/2006:15:37:02 +0800] [Job 7] GhostScript extra search path ('GS_LIB'): /usr/share/cups/fonts
D [28/May/2006:15:37:02 +0800] [Job 7] Pondering option 'job-uuid=urn:uuid:8e273b75-64a3-366c-785d-6ccc64536ff8'
D [28/May/2006:15:37:02 +0800] [Job 7] Unknown option job-uuid=urn:uuid:8e273b75-64a3-366c-785d-6ccc64536ff8.
D [28/May/2006:15:37:02 +0800] [Job 7]
D [28/May/2006:15:37:02 +0800] [Job 7] ================================================
D [28/May/2006:15:37:02 +0800] [Job 7]
D [28/May/2006:15:37:02 +0800] [Job 7] File: <STDIN>
D [28/May/2006:15:37:02 +0800] [Job 7]
D [28/May/2006:15:37:02 +0800] [Job 7] ================================================
D [28/May/2006:15:37:02 +0800] [Job 7]
D [28/May/2006:15:37:02 +0800] [Job 7] Reading PostScript input ...
D [28/May/2006:15:37:02 +0800] [Job 7] --> This document is DSC-conforming!
D [28/May/2006:15:37:02 +0800] [Job 7]
D [28/May/2006:15:37:02 +0800] [Job 7] -----------
D [28/May/2006:15:37:02 +0800] [Job 7] Found: %%BeginProlog
D [28/May/2006:15:37:02 +0800] [Job 7] Found: %%EndProlog
D [28/May/2006:15:37:02 +0800] [Job 7]
D [28/May/2006:15:37:02 +0800] [Job 7] -----------
D [28/May/2006:15:37:02 +0800] [Job 7] Found: %%BeginSetup
D [28/May/2006:15:37:02 +0800] [Job 7] Found: %%BeginFeature: *PageRegion A4
D [28/May/2006:15:37:02 +0800] [Job 7] Option: PageRegion=A4 --> Option will be set by PostScript interpreter
D [28/May/2006:15:37:02 +0800] [Job 7] Found: %% FoomaticRIPOptionSetting: PageSize=A4
D [28/May/2006:15:37:02 +0800] [Job 7] Option: PageSize=A4 --> Setting option
D [28/May/2006:15:37:02 +0800] [Job 7] Found: %%BeginFeature: *Resolution 600x600dpi
D [28/May/2006:15:37:02 +0800] [Job 7] Option: Resolution=600x600dpi --> Setting option
D [28/May/2006:15:37:02 +0800] [Job 7] Found: %% FoomaticRIPOptionSetting: Resolution=600x600dpi
D [28/May/2006:15:37:02 +0800] [Job 7] Option: Resolution=600x600dpi --> Setting option
D [28/May/2006:15:37:02 +0800] [Job 7] Found: %%BeginFeature: *MediaType Normal
D [28/May/2006:15:37:02 +0800] [Job 7] Option: MediaType=Normal --> Setting option
D [28/May/2006:15:37:02 +0800] [Job 7] Found: %% FoomaticRIPOptionSetting: MediaType=Normal
D [28/May/2006:15:37:02 +0800] [Job 7] Option: MediaType=Normal --> Setting option
D [28/May/2006:15:37:02 +0800] [Job 7] Found: %%BeginFeature: *InputSlot Default
D [28/May/2006:15:37:02 +0800] [Job 7] Option: InputSlot=Default --> Setting option
D [28/May/2006:15:37:02 +0800] [Job 7] Found: %% FoomaticRIPOptionSetting: InputSlot=Default
D [28/May/2006:15:37:02 +0800] [Job 7] Option: InputSlot=Default --> Setting option
D [28/May/2006:15:37:02 +0800] [Job 7] Found: %%BeginFeature: *Economode Off
D [28/May/2006:15:37:02 +0800] [Job 7] Option: Economode=Off --> Setting option
D [28/May/2006:15:37:02 +0800] [Job 7] Found: %% FoomaticRIPOptionSetting: Economode=Off
D [28/May/2006:15:37:02 +0800] [Job 7] Option: Economode=Off --> Setting option
D [28/May/2006:15:37:02 +0800] [Job 7] Found: %%EndSetup
D [28/May/2006:15:37:02 +0800] [Job 7] Inserting PostScript code for CUPS' page accounting
D [28/May/2006:15:37:02 +0800] [Job 7]
D [28/May/2006:15:37:02 +0800] [Job 7] -----------
D [28/May/2006:15:37:02 +0800] [Job 7] New page:  1 1
D [28/May/2006:15:37:02 +0800] [Job 7] Inserting option code into "PageSetup" section.
D [28/May/2006:15:37:02 +0800] [Job 7]
D [28/May/2006:15:37:02 +0800] [Job 7] Found: %%BeginPageSetup
D [28/May/2006:15:37:02 +0800] [Job 7] Found: %%EndPageSetup
D [28/May/2006:15:37:02 +0800] [Job 7] End of page header
D [28/May/2006:15:37:02 +0800] [Job 7] Embedded document, nesting level now: 1
D [28/May/2006:15:37:02 +0800] [Job 7] Stopping search for page header options
D [28/May/2006:15:37:02 +0800] [Job 7] Found:
D [28/May/2006:15:37:02 +0800] [Job 7] 48E62B95341CD8FBFF9CF7500810292C59FB187EA6D149392A3C896C4A8636D8E124EEBC8EED9E950B5933BD7CC062C8702BD71A3F6DC4040EF513405D71A1206BAE2E5D35FE7473BB9145CC43E785C0079B2F4693F0DC1AC005B9ABBEF411E733B0
D [28/May/2006:15:37:02 +0800] [Job 7] --> Output goes directly to the renderer now.
D [28/May/2006:15:37:02 +0800] [Job 7]
D [28/May/2006:15:37:02 +0800] [Job 7]
D [28/May/2006:15:37:02 +0800] [Job 7] Starting renderer
D [28/May/2006:15:37:02 +0800] [Job 7] JCL: <job data>
D [28/May/2006:15:37:02 +0800] [Job 7]
D [28/May/2006:15:37:02 +0800] [Job 7] renderer PID kid4=15306
D [28/May/2006:15:37:02 +0800] [Job 7] renderer command: gs -q -dNOPAUSE -dPARANOIDSAFER -dBATCH -sDEVICE=pbmraw -dDEVICEWIDTHPOINTS=595 -dDEVICEHEIGHTPOINTS=842 -r600 -sOutputFile=- - | min12xxw -m 1350W -f a4 -r 600 -p normal -t auto
D [28/May/2006:15:37:02 +0800] [Job 7] perl: warning: Setting locale failed.
D [28/May/2006:15:37:02 +0800] [Job 7] perl: warning: Please check that your locale settings:
D [28/May/2006:15:37:02 +0800] [Job 7] LANGUAGE = (unset),
D [28/May/2006:15:37:02 +0800] [Job 7] LC_ALL = (unset),
D [28/May/2006:15:37:02 +0800] [Job 7] LANG = "en_US"
D [28/May/2006:15:37:02 +0800] [Job 7] are supported and installed on your system.
D [28/May/2006:15:37:02 +0800] [Job 7] perl: warning: Falling back to the standard locale ("C").
D [28/May/2006:15:37:02 +0800] [Job 7] foomatic-gswrapper: gs '-dNOPAUSE' '-dPARANOIDSAFER' '-dBATCH' '-sDEVICE=pbmraw' '-dDEVICEWIDTHPOINTS=595' '-dDEVICEHEIGHTPOINTS=842' '-r600' '-sOutputFile=/dev/fd/3' '/dev/fd/0' 3>&1 1>&2
D [28/May/2006:15:37:03 +0800] [Job 7] ESP Ghostscript 815.02 (2006-04-19)
D [28/May/2006:15:37:03 +0800] [Job 7] Copyright (C) 2004 artofcode LLC, Benicia, CA.  All rights reserved.
D [28/May/2006:15:37:03 +0800] [Job 7] This software comes with NO WARRANTY: see the file PUBLIC for details.
D [28/May/2006:15:37:03 +0800] [Job 7] Loading NimbusSanL-Regu font from /var/lib/defoma/gs.d/dirs/fonts/n019003l.pfb... 2352144 931584 1476580 176414 1 done.
D [28/May/2006:15:37:03 +0800] [Job 7] Wrote 1 pages...
D [28/May/2006:15:37:03 +0800] PID 15301 (/usr/lib/cups/filter/pstops) exited with no errors.
D [28/May/2006:15:37:03 +0800] [Job 7] End of Embedded document, nesting level now: 0
D [28/May/2006:15:37:03 +0800] [Job 7]
D [28/May/2006:15:37:03 +0800] [Job 7] Closing renderer
...
D [28/May/2006:15:37:07 +0800] [Job 7] LPGETSTATUS returned a port status of 08...
W [28/May/2006:15:37:07 +0800] [Job 7] Printer off-line.
...
D [28/May/2006:15:37:12 +0800] [Job 7] LPGETSTATUS returned a port status of 08...
W [28/May/2006:15:37:12 +0800] [Job 7] Printer off-line.


Even at the moment cups is reporting Printer off-line, the previous chain of commands can still print to the printer.


/etc/cups/printers.conf:
<DefaultPrinter PagePro-1350W>
Info PagePro-1350W
DeviceURI usb://KONICA%20MINOLTA/PP1350W
State Idle
StateTime 1146815600
Accepting Yes
Shared Yes
JobSheets none none
QuotaPeriod 0
PageLimit 0
KLimit 0
OpPolicy default
ErrorPolicy abort-job
</Printer>