Difficulty connecting to "open" wireless network with MBP

Hi

I'm having difficulty using an open wireless network with both my iPhone and MacBook. My windows and Palm-using buddies don't seem to have any problems.

On the network in question, guest users must click through a "terms of use" splash page, but no formal log in or password is required. Both the iPhone and Powerbook do see, and appear to connect to the network, but internet access never occurs. The splash page that auto-loads on the windows machines never opens. I have enabled "accept cookies" and "allow pop-ups". I've tried using alternative browsers on the MacBook, but no luck. Any ideas?

Thanks in advance!