WordPress comment problems

Hi there. I hawe a preaty big problem. I’m using WordPress couple years ago, but this is the first problem that i can’t resolve.

I hawe started a new blog few months ago at THIS domain. Until now all was ok but now, i can’t activate the comment option. From the start in the admin panel it’s activated, there are few comments to, but now nothing. It’s still active but in the posts footer it’s written that comments are turned off. In the Write page de “Pings and comments” module it’s gone. I hawe tryed to deactivate all plugins to see what it’s the problem but nothing.
Please help, me my users can’t post comments to my posts and i need that comment :). My blog and the theme on it it’s hungaryan, but there’s an english WP 2.5.1.

Please help me, and forgiwe me my bad english.
Thank you.