Problem with ipw3945 & "Detected geography ABG"

Hello all,

I'm using Ubuntu Devel distribution (Feisty) and i have a problem with me wifi 
card witch use ipw driver.

Randomly, my connection stops and returns a few minutes (hours ?) later.
When my connection is off, I can see this in my logs (syslog & messages) :

......
Dec  5 10:44:52 localhost kernel: [13772.413009] ipw3945: Detected geography 
ABG (13 802.11bg channels, 23 802.11a channels)
Dec  5 10:45:00 localhost kernel: [13780.016836] ipw3945: Detected geography 
ABG (13 802.11bg channels, 23 802.11a channels)
Dec  5 10:45:07 localhost kernel: [13787.620686] ipw3945: Detected geography 
ABG (13 802.11bg channels, 23 802.11a channels)
Dec  5 10:45:15 localhost kernel: [13795.224504] ipw3945: Detected geography 
ABG (13 802.11bg channels, 23 802.11a channels)
Dec  5 10:45:23 localhost kernel: [13802.832364] ipw3945: Detected geography 
ABG (13 802.11bg channels, 23 802.11a channels)
Dec  5 10:45:30 localhost kernel: [13810.436194] ipw3945: Detected geography 
ABG (13 802.11bg channels, 23 802.11a channels)
Dec  5 10:45:38 localhost kernel: [13818.040050] ipw3945: Detected geography 
ABG (13 802.11bg channels, 23 802.11a channels)
Dec  5 10:45:45 localhost kernel: [13825.643897] ipw3945: Detected geography 
ABG (13 802.11bg channels, 23 802.11a channels)
......

It's very irritating especially that the connexion returns all alone, without 
doing anything. For this period, impossible to discharge the module ipw3945. 
The only solution to find a connection is to reboot again the machine.

Is anyone know what can i do to solve this issus ?
Must i report a bug ? and where ? ubuntu ? ipw project ?

Please, help me :)

Info :

lspci :
root@portable:/home/yannick# lspci |grep -i "network"
03:00.0 Network controller: Intel Corporation PRO/Wireless 3945ABG Network 
Connection (rev 02)

uname :
root@portable:/home/yannick# uname -a
Linux portable 2.6.19-7-generic #2 SMP Mon Dec 4 16:46:19 UTC 2006 i686 
GNU/Linux

lsmod :
root@portable:/home/yannick# lsmod |grep -i "ipw"
ipw3945               124832  1
ieee80211              35528  1 ipw3945



PS : PLease, CC me, i'm not member to this mailing-lists.
PS 2 : Sorry for my bad english, I'm french ... :)
-- 
Yannick