iwl3945 slow for downloading

["Cédric Auger" <cedric@grisbi.org>]

hello
i've a problem for iwl3945 and didn't find on google something about
that. i have the kernel 2.6.26 and use the kernel's driver. when i was
with the ipw3945, i could download with a speed of at least 600k/s, and
sometimes more.
it's some time i changed for iwl3945 and didn't see some difference
exept it works better in several ways, but some times ago, i noticed
that dowloading big images was slow.
i checked to transfer a file between 2 computer by wifi, and the
download is limited to about 130-140k/s. when i plug a cable, i go
directly to 900kb/s.
i tried to remove all debugging options in the kernel for that driver,
but no differences.
i don't see any difference when i go on website, it's only the max
download speed wich cannot go more thant 130kb/s.
i have a dell m1710, with intel 3945ABG
my lspci :
0c:00.0 Network controller: Intel Corporation PRO/Wireless 3945ABG
Network Connection (rev 02)
i'm on debian sid, with a 2.6.26 kernel and use wpa supplicant
i have networkmanager as daemon, but use /etc/network/interfaces and
ifup to manage my wifi
i have no error on my syslog, daemon.log, wpa_supplicant log,
i don't know if you need some extra informations about my system.
thanks
cedric