Wireless LAN IP Problem

hY
I recently bought 2 wireless MSI cards and a wireless router. The network works fine on windows but on linux i have serious problems whit the network IP, i can connect to the router but i cant get an IP adress, the router as DHCP activated, as far as can see the router is okay.
Im running Linux Slackware 10, i've try the netconfig script, configure it to work whit static and with DHCP but none worked, th hardware is working fine as far as i know, the modules load up just right, the wireless card can connect to the router but it cant get an IP. Need Help

Thanks
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