Hmmm, most odd. There is certainly nothing in the forum settings about a mobile layout that could be set, or at least I've not seen anything.
I do remember when I last tried the forum with Safari on my Iphone things were a bit weerd, but I've never exactly found Safari that efficient as a browser. It wont' interact with the combo dropdown box on the front page at all but just displays all the games as a list and always starts at the bottom, heck I couldn't even make posts because I wasn't able to hit the submit button. And the time I tried to play Core exiles was an out right disaster (it's just plane crazy with images and alt text, or at least was last I tried).
This is why I don't tend to use my phone for web browsing much, still as I said as far as I know the forum shouldn't be adapting to what your browsing it on anyway.
With our dreaming and singing, Ceaseless and sorrowless we! The glory about us clinging Of the glorious futures we see,
Our souls with high music ringing; O men! It must ever be
That we dwell in our dreaming and singing, A little apart from ye. (Arthur O'Shaughnessy 1873.)