You should find out what wifi card there is in your machine. Since the button is properly hook directly to either the hardware or the kernel module.
To find out what module (driver) your wifi uses you can run the command
sudo lshw and find a section looks like this one:
description: Wireless interface
product: PRO/Wireless 2200BG [Calexico2] Network Connection
vendor: Intel Corporation
physical id: 2
bus info: pci@0000:0b:02.0
logical name: eth1
width: 32 bits
capabilities: pm bus_master cap_list ethernet physical wireless
configuration: broadcast=yes driver=ipw2200 driverversion=1.2.2kmprq firmware=ABG:188.8.131.52 (Dec 12 2007) ip=192.168.2.3 latency=64 link=yes maxlatency=24 mingnt=3 multicast=yes wireless=IEEE 802.11g
resources: irq:21 memory:b4001000-b4001fff
configuration: line it says what the driver is, in the example ipw2200. Without this info there is no way to know where to report the bug.
The iwlagn module has recently been merged into the main-line kernel, so there is multiple places to report bugs (and maybe find fixes) Have a look at http://bugzilla.intellinuxwireless.org/ and https://bugs.launchpad.net/ubuntu/+source/linux try to find out if the bug is already reported. If it is reported there might be some comments that can be help full.
If it isn't reported you should have a look at https://help.ubuntu.com/community/ReportingBugs and then file a bug report your self.