Hello,
Same problem here in Ubuntu 9.10 / 64b
Symtpom : Freeze and led blinking

kern.log :
Nov 29 22:46:40 alberto-laptop kernel: [  470.663710] iwlagn 0000:03:00.0: iwl_tx_agg_start on ra = ee:40:00:73:33:00 tid = 0
Nov 29 22:49:32 alberto-laptop kernel: [  642.661432] iwlagn 0000:03:00.0: iwl_tx_agg_start on ra = ee:40:00:73:33:00 tid = 6
Nov 29 22:51:01 alberto-laptop kernel: [  732.180057] CE: hpet increasing min_delta_ns to 15000 nsec
Nov 29 22:52:02 alberto-laptop kernel: [  793.102574] CE: hpet increasing min_delta_ns to 22500 nsec
Nov 29 22:54:44 alberto-laptop kernel: [  955.204926] CE: hpet increasing min_delta_ns to 33750 nsec
Nov 29 23:10:02 alberto-laptop kernel: imklog 4.2.0, log source = /var/run/rsyslog/kmsg started.
Nov 29 23:10:02 alberto-laptop kernel: [    0.000000] Initializing cgroup subsys cpuset
Nov 29 23:10:02 alberto-laptop kernel: [    0.000000] Initializing cgroup subsys cpu

uname -a
Linux alberto-laptop 2.6.31-15-generic #50-Ubuntu SMP Tue Nov 10 14:53:52 UTC 2009 x86_64 GNU/Linux

cpuinfo
model name	: Intel(R) Core(TM)2 Duo CPU     T6400  @ 2.00GHz

dmesg
[   20.364690] iwlagn 0000:03:00.0: firmware: requesting iwlwifi-5000-2.ucode
[   20.665265] iwlagn 0000:03:00.0: loaded firmware version 8.24.2.12
[   20.815123] Registered led device: iwl-phy0::radio
[   20.815150] Registered led device: iwl-phy0::assoc
[   20.815177] Registered led device: iwl-phy0::RX
[   20.815204] Registered led device: iwl-phy0::TX
[   20.851109] ADDRCONF(NETDEV_UP): wlan0: link is not ready
[   22.501756] ppdev: user-space parallel port driver
[   25.032597] CE: hpet increasing min_delta_ns to 15000 nsec
[   25.032691] CE: hpet increasing min_delta_ns to 22500 nsec
[   27.442548] hda-intel: azx_get_response timeout, switching to polling mode: last cmd=0x016f000c
[   28.252615] CE: hpet increasing min_delta_ns to 33750 nsec
[   71.846796] wlan0: authenticate with AP ee:40:00:73:33:00

lspci
00:00.0 Host bridge: Intel Corporation Mobile 4 Series Chipset Memory Controller Hub (rev 07)
00:01.0 PCI bridge: Intel Corporation Mobile 4 Series Chipset PCI Express Graphics Port (rev 07)
00:1a.0 USB Controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #4 (rev 03)
00:1a.1 USB Controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #5 (rev 03)
00:1a.2 USB Controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #6 (rev 03)
00:1a.7 USB Controller: Intel Corporation 82801I (ICH9 Family) USB2 EHCI Controller #2 (rev 03)
00:1b.0 Audio device: Intel Corporation 82801I (ICH9 Family) HD Audio Controller (rev 03)
00:1c.0 PCI bridge: Intel Corporation 82801I (ICH9 Family) PCI Express Port 1 (rev 03)
00:1c.1 PCI bridge: Intel Corporation 82801I (ICH9 Family) PCI Express Port 2 (rev 03)
00:1c.2 PCI bridge: Intel Corporation 82801I (ICH9 Family) PCI Express Port 3 (rev 03)
00:1d.0 USB Controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #1 (rev 03)
00:1d.1 USB Controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #2 (rev 03)
00:1d.2 USB Controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #3 (rev 03)
00:1d.7 USB Controller: Intel Corporation 82801I (ICH9 Family) USB2 EHCI Controller #1 (rev 03)
00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev 93)
00:1f.0 ISA bridge: Intel Corporation ICH9M LPC Interface Controller (rev 03)
00:1f.2 IDE interface: Intel Corporation ICH9M/M-E 2 port SATA IDE Controller (rev 03)
00:1f.5 IDE interface: Intel Corporation ICH9M/M-E 2 port SATA IDE Controller (rev 03)
01:00.0 VGA compatible controller: nVidia Corporation G96 [GeForce 9600M GS] (rev a1)
02:00.0 Ethernet controller: Broadcom Corporation NetLink BCM5906M Fast Ethernet PCI Express (rev 02)
03:00.0 Network controller: Intel Corporation PRO/Wireless 5100 AGN [Shiloh] Network Connection
07:03.0 FireWire (IEEE 1394): Ricoh Co Ltd R5C832 IEEE 1394 Controller (rev 05)
07:03.1 SD Host controller: Ricoh Co Ltd R5C822 SD/SDIO/MMC/MS/MSPro Host Adapter (rev 22)
07:03.2 System peripheral: Ricoh Co Ltd R5C843 MMC Host Controller (rev 12)
07:03.3 System peripheral: Ricoh Co Ltd R5C592 Memory Stick Bus Host Adapter (rev 12)
07:03.4 System peripheral: Ricoh Co Ltd xD-Picture Card Controller (rev ff)

Any idea other?