I've been fighting this problem for two weeks.
Host is UIA (uia.net), no cpanel.
Install went fine, and WP is connected to the database. When I try to initiate a new post, I get the dreaded blank screen (no posting interface). However, I do get the right hand publish menu, and if I just hit the "save draft" button, it creates a blank post that I can then go into the edit.php and edit via the interface. In other words, the posting interface shows up in edit.php, but doesn't in post-new.php.
Tech support at UIA says they're seeing a "stack overload" error when post-new.php loads. They've been very little help in resolving the issue. Switching hosts is not an option at this time, as I have a Joomla installation running on the same server, same domain. I'm trying to get a client off Joomla and over to WP, but this is sure giving him a sour first impression of WP.
No plugins are enabled, running twenty-ten theme, new download of 3.1.2, all straight out of the box. The same issue was happening in 3.1.1 prior to upgrading. Help or ideas sincerely appreciated! We've flushed the database completely, and did a fresh install. Same problem.