Same problem using an updated 2.6.20 kernel on an HP 500 notebook.

dmesg says :
[   75.572000] [drm] Initialized drm 1.1.0 20060810
[   75.620000] ACPI: PCI Interrupt 0000:00:02.0[A] -> GSI 16 (level, low) -> IRQ 19
[   75.620000] [drm] Initialized i915 1.6.0 20060119 on minor 0
[   88.184000] eth0: no IPv6 routers present
[  687.500000] ata1.01: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2 frozen
[  687.500000] ata1.01: cmd a0/00:00:00:00:20/00:00:00:00:00/b0 tag 0 cdb 0x0 data 0 
[  687.500000]          res 40/00:03:00:00:00/00:00:00:00:00/b0 Emask 0x4 (timeout)
[  694.500000] ata1: port is slow to respond, please be patient (Status 0xd0)
[  717.516000] ata1: port failed to respond (30 secs, Status 0xd0)
[  717.516000] ata1: soft resetting port
[  717.868000] ata1.00: configured for UDMA/100
[  718.048000] ata1.01: configured for MWDMA2
[  718.048000] ata1: EH complete
[  718.064000] SCSI device sda: 117210240 512-byte hdwr sectors (60012 MB)
[  718.064000] sda: Write Protect is off
[  718.064000] sda: Mode Sense: 00 3a 00 00
[  718.064000] SCSI device sda: write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[  718.064000] SCSI device sda: 117210240 512-byte hdwr sectors (60012 MB)
[  718.064000] sda: Write Protect is off
[  718.064000] sda: Mode Sense: 00 3a 00 00
[  718.064000] SCSI device sda: write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[ 1673.024000] ata1.01: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2 frozen
[ 1673.024000] ata1.01: cmd a0/00:00:00:00:20/00:00:00:00:00/b0 tag 0 cdb 0x0 data 0 
[ 1673.024000]          res 40/00:03:00:00:00/00:00:00:00:00/b0 Emask 0x4 (timeout)
[ 1680.024000] ata1: port is slow to respond, please be patient (Status 0xd0)
[ 1703.040000] ata1: port failed to respond (30 secs, Status 0xd0)
[ 1703.040000] ata1: soft resetting port
[ 1703.392000] ata1.00: configured for UDMA/100
[ 1703.572000] ata1.01: configured for MWDMA2
[ 1703.572000] ata1: EH complete
[ 1703.588000] SCSI device sda: 117210240 512-byte hdwr sectors (60012 MB)
[ 1703.588000] sda: Write Protect is off
[ 1703.588000] sda: Mode Sense: 00 3a 00 00
[...]

$ lspci
00:00.0 Host bridge: Intel Corporation Mobile 915GM/PM/GMS/910GML Express Processor to DRAM Controller (rev 03)
00:02.0 VGA compatible controller: Intel Corporation Mobile 915GM/GMS/910GML Express Graphics Controller (rev 03)
00:02.1 Display controller: Intel Corporation Mobile 915GM/GMS/910GML Express Graphics Controller (rev 03)
00:1d.0 USB Controller: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) USB UHCI #1 (rev 03)
00:1d.7 USB Controller: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) USB2 EHCI Controller (rev 03)
00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev d3)
00:1e.2 Multimedia audio controller: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) AC'97 Audio Controller (rev 03)
00:1e.3 Modem: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) AC'97 Modem Controller (rev 03)
00:1f.0 ISA bridge: Intel Corporation 82801FBM (ICH6M) LPC Interface Bridge (rev 03)
00:1f.1 IDE interface: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) IDE Controller (rev 03)
02:04.0 Network controller: Intel Corporation PRO/Wireless 2200BG Network Connection (rev 05)
02:06.0 CardBus bridge: ENE Technology Inc CB1410 Cardbus Controller (rev 01)
02:08.0 Ethernet controller: Intel Corporation PRO/100 VE Network Connection (rev 03)