Hello.

dhclient-script (Linux version) puts the interface down on some
circunstances, to flush caches and routes.  At least some wireless drivers
lose association when the interface is put down.  Also, at least some (the
same) drivers fail to signal deassociation when the interface is put down. 
So we get to Mandriva bug 43441.  Please see comment 13 and 41 here:
<https://qa.mandriva.com/show_bug.cgi?id=43441#c13>,
<https://qa.mandriva.com/show_bug.cgi?id=43441#c41>

As stated on #c41, Andrey Borzenkov pointed out "ifconfig inet 0" is enough. 
I also found Debian (+ Ubuntu) has this same fix since 2005 on their own
script (<http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=323254>) which
should demonstrate it works.

If you don't see problems with this, I believe this should be fixed in your
codebase.  Little patch (so far without the "ifconfig up" fix, present in
Debian's) here:
<http://svn.mandriva.com/cgi-bin/viewvc.cgi/packages/cooker/dhcp/current/SOURCES/dhcp-4.1.0-prevent_wireless_deassociation.patch?view=log>

Cc'ing our dhcp maintainer and Andrey, for refs. Please keep the Cc list on
replies unless stated otherwise.

Thanks.