Admin tool question

When I log into my wirless gateway using the admin tool and go to the section called LAN, it shows my ethernet ports. There are four of them however under each ethernet port it says "Mac Address Down" My internet works fine and I got devices hardwired, they work but I wonder why does it say Mac Address Down? Is this some sort of a glitch? I called Comcast about it a while back but they didn't fix it. 

Thanks