MAC address filtering on iPad on DSL router

At home I have an Airport Extreme router and both WPA-2 encryption and MAC address filtering work just fine on both my MacBook Pro laptop and on my new iPad... But then I headed off to visit my dad in another part of the country. He has ATT DSL with a 2-Wire 2701HB-G router... I have both my MacBook Pro and my iPad with me... Setting up WPA-2 encryption worked fine and MAC address filtering also works fine on my MacBook Pro... But that doesn't work at all on my iPad... I have followed the very simple instructions that the 2701HB-G offers to enable MAC address filtering but each time I enable it, the iPad loses connection... Disable MAC filtering and the iPad immediately regains connection... I've even let the 2701HB-G go out and find its own list of available machines to allow under MAC address filtering... It sees the iPad by the name I gave it but even that method fails when I accept that list and enable MAC address filtering... I've also tried completely rebooting the router and restarting the iPad but simply stated, whatever I try causes the iPad to lose connectivity the moment I turn on MAC address filtering... All the while my MacBoo Pro connects just fine with MAC address filtering on... Any thoughts???? And is it true that MAC address filtering doesn't really offer much protection anyway??? Especially considering I do have WPA-2 protection turned on???

thanks... bob..