This is a bit of an odd one and was wondering if anyone had a solution.
We're building a few websites just now that are over 1000px in width and for some reason when the iPad loads them up in portrait mode it's scaling them down but leaving some width on the right so you have to scroll just a little over to see everything.
I added <meta name="viewport" content="initial-scale=0.7;" />
which does fix the problem but when loaded in landscape the user is presented with a small site to start with and can zoom out too far.
An example of this can be seen on one of my personal development sites. This isn't live yet so please ignore any bugs http://www.dundeewebstandards.com/events/
Thanks,
Chris