Epson USB scanner doesn't work

Hi,

I try using my Epson USB Scanner with FreeBSD 5.3beta2, but it's only 
possible to communitcate with the scanner and sane one time then it 
hangs. The scanner is listed as supported (GT-7000 is the european model 
of the Perfection 636U).

bash-3.00# scanimage -L
device `epson:/dev/uscanner0' is a Epson GT-7000 flatbed scanner
bash-3.00# scanimage -L
^C
bash-3.00# scanimage -L
^C

These are the last lines of the debug output befor scanimage hangs:

Aug 30 23:09:12 notebook kernel: uscanner0: uscannerread
Aug 30 23:09:12 notebook kernel: uscannerread: start transfer 1 bytes
Aug 30 23:09:12 notebook kernel: usbd_bulk_transfer: start transfer 1 bytes
Aug 30 23:09:12 notebook kernel: usbd_transfer: xfer=0xc206c100, 
flags=4, pipe=0xc2516a00, running=0
Aug 30 23:09:12 notebook kernel: usbd_dump_queue: pipe=0xc2516a00
Aug 30 23:09:12 notebook kernel: usb_allocmem: use frag=0xc1667f40 size=1
Aug 30 23:09:12 notebook kernel: usb_insert_transfer: pipe=0xc2516a00 
running=0 timeout=0
Aug 30 23:09:12 notebook kernel: uhci_device_bulk_start: xfer=0xc206c100 
len=1 flags=4 ii=0xc206c170
Aug 30 23:09:12 notebook kernel: uhci_alloc_std_chain: addr=2 endpt=1 
len=1 speed=2 flags=0x4
Aug 30 23:09:12 notebook kernel: uhci_alloc_std_chain: maxp=64 ntd=1
Aug 30 23:09:12 notebook kernel: uhci_alloc_std_chain: nexttog=1
Aug 30 23:09:12 notebook kernel: uhci_device_bulk_transfer: data(1)
Aug 30 23:09:12 notebook kernel: TD(0xc1643f80) at 001b7f80 = 
link=0x00000005 status=0x398003ff token=0x00008269 buffer=0x0023bf40
Aug 30 23:09:12 notebook kernel: 5<T,VF> 
398003ff<ACTIVE,IOC,SPD>,errcnt=3,actlen=0 
pid=69,addr=2,endpt=1,D=0,maxlen=1
Aug 30 23:09:12 notebook kernel: uhci_add_bulk: sqh=0xc1642f20
Aug 30 23:09:12 notebook kernel: uhci_start_loop: add
Aug 30 23:09:12 notebook kernel: uhci_device_bulk_transfer: data(2)
Aug 30 23:09:12 notebook kernel: TD(0xc1643f80) at 001b7f80 = 
link=0x00000005 status=0x398003ff token=0x00008269 buffer=0x0023bf40
Aug 30 23:09:12 notebook kernel: 5<T,VF> 
398003ff<ACTIVE,IOC,SPD>,errcnt=3,actlen=0 
pid=69,addr=2,endpt=1,D=0,maxlen=1

Does anyone have a clue what happen to cause this?

Thanks in advance
Roland