After not having any problems for quite some time the problem reappeared.

Ubuntu 8.04, Kernel 2.6.24-19-generic
Nikon D40 Firmware 1.11

There was a firmware upgrade recently, but it definitely worked for a while.

This is the dmesg output:

[32518.038002] usb 4-3: new high speed USB device using ehci_hcd and address 9
[32518.172783] usb 4-3: configuration #1 chosen from 1 choice
[32518.278078] scsi5 : SCSI emulation for USB Mass Storage devices
[32518.289552] usb-storage: device found at 9
[32518.289563] usb-storage: waiting for device to settle before scanning
[32528.279782] usb-storage: device scan complete
[32528.281077] scsi 5:0:0:0: Direct-Access     NIKON    D40              1.11 PQ: 0 ANSI: 2
[32528.296886] sd 5:0:0:0: [sdb] 3970049 512-byte hardware sectors (2033 MB)
[32528.297647] sd 5:0:0:0: [sdb] Write Protect is off
[32528.297657] sd 5:0:0:0: [sdb] Mode Sense: 0f 00 00 00
[32528.297665] sd 5:0:0:0: [sdb] Assuming drive cache: write through
[32528.301893] sd 5:0:0:0: [sdb] 3970049 512-byte hardware sectors (2033 MB)
[32528.302642] sd 5:0:0:0: [sdb] Write Protect is off
[32528.302652] sd 5:0:0:0: [sdb] Mode Sense: 0f 00 00 00
[32528.302659] sd 5:0:0:0: [sdb] Assuming drive cache: write through
[32528.302668]  sdb: sdb1
[32528.305639] sd 5:0:0:0: [sdb] Attached SCSI removable disk
[32528.305738] sd 5:0:0:0: Attached scsi generic sg2 type 0
[10836.641856] end_request: I/O error, dev sdb, sector 3970048
[10836.641862] printk: 237 messages suppressed.
[10836.641865] Buffer I/O error on device sdb, logical block 3970048
[10836.643478] end_request: I/O error, dev sdb, sector 3970048
[10836.643481] Buffer I/O error on device sdb, logical block 3970048
[10836.648623] end_request: I/O error, dev sdb, sector 3970048
[10836.648627] Buffer I/O error on device sdb, logical block 3970048
[10836.649974] end_request: I/O error, dev sdb, sector 3970048
[10836.649978] Buffer I/O error on device sdb, logical block 3970048
[10836.651735] end_request: I/O error, dev sdb, sector 3970048
[10836.651739] Buffer I/O error on device sdb, logical block 3970048
[10836.664092] end_request: I/O error, dev sdb, sector 3970048
[10836.664099] Buffer I/O error on device sdb, logical block 3970048
[10836.665591] end_request: I/O error, dev sdb, sector 3970048
[10836.665596] Buffer I/O error on device sdb, logical block 3970048
[10836.667117] end_request: I/O error, dev sdb, sector 96
[10836.667122] Buffer I/O error on device sdb, logical block 96
[10836.668463] end_request: I/O error, dev sdb, sector 97
[10836.668467] Buffer I/O error on device sdb, logical block 97
[10836.668470] Buffer I/O error on device sdb, logical block 98
[10836.669961] end_request: I/O error, dev sdb, sector 96
[10836.671224] end_request: I/O error, dev sdb, sector 97
[10836.743792] end_request: I/O error, dev sdb, sector 0
[10836.745787] end_request: I/O error, dev sdb, sector 0
[10836.746912] end_request: I/O error, dev sdb, sector 1
[10836.748660] end_request: I/O error, dev sdb, sector 0
[10836.749784] end_request: I/O error, dev sdb, sector 1
[10836.755290] end_request: I/O error, dev sdb, sector 249
[10836.756657] end_request: I/O error, dev sdb, sector 249
[10836.757916] end_request: I/O error, dev sdb, sector 250
[10836.814623] end_request: I/O error, dev sdb, sector 249
[10836.817249] end_request: I/O error, dev sdb, sector 249
[10836.818491] end_request: I/O error, dev sdb, sector 250
[10836.820616] end_request: I/O error, dev sdb, sector 0
[10836.821865] end_request: I/O error, dev sdb, sector 1
[10836.823323] end_request: I/O error, dev sdb, sector 0
[10836.824612] end_request: I/O error, dev sdb, sector 1
[10836.825873] end_request: I/O error, dev sdb, sector 0
[10836.827230] end_request: I/O error, dev sdb, sector 1


This is what lsusb -v gives:
Bus 004 Device 009: ID 04b0:0413 Nikon Corp. D40 (mass storage mode)
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass            0 (Defined at Interface level)
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0        64
  idVendor           0x04b0 Nikon Corp.
  idProduct          0x0413 D40 (mass storage mode)
  bcdDevice            1.11
  iManufacturer           1 NIKON
  iProduct                2 NIKON DSC D40
  iSerial                 3 XXXXXX
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength           32
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xc0
      Self Powered
    MaxPower                2mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           2
      bInterfaceClass         8 Mass Storage
      bInterfaceSubClass      6 SCSI
      bInterfaceProtocol     80 Bulk (Zip)
      iInterface              0 
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x02  EP 2 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               0
Device Qualifier (for other device speed):
  bLength                10
  bDescriptorType         6
  bcdUSB               2.00
  bDeviceClass            0 (Defined at Interface level)
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0        64
  bNumConfigurations      1
Device Status:     0x0001
  Self Powered

Is there hope that this issue can be resolved once for all time?