[@netweb Keymaster 13 years, 6 months ago]

Is this WordPress MultiSite setup or two separate WordPress installs for each of your domains?

Either way neither is a known issue and should work as you expect it would.

Try switching the problem site to the Twenty Theme and disable any other plugins to see if there is a conflict some, re-enable each plugin one by one and test your site again to see if you can find the conflicting plugin.