Are you running wireless security on your router? I seem to recall some folks talking about problems with the way different phones handle certain wireless security implementations. Can't remember which thread. A forum or google search may prove useful.
While you're waiting for others to test for you. You might take your phone to a different wifi(like starbucks or ...) and test again.
EDIT: Although not about wireless security, this thread talks about a user disabling wireless N on the router. Cisco/Linksys WRVS4400N 2.0