I have just noticed that all of a sudden, my newbb is kinda messed up... when you post a message, it adds it to the site, but the post.php displays an empty page afterwards... what i get is, people submitting, getting an empty screen and pressing "refresh" in their browser resulting in the message being added yet again... what's the problem here?

I've already uploaded the whole newbb directory again, to no avail

What does PHP debug tell you?

Notice [PHP]: Undefined index: nosmiley in file modules/newbb/post.php line 166
Notice [PHP]: Undefined index: icon in file modules/newbb/post.php line 167
Notice [PHP]: Undefined index: attachsig in file modules/newbb/post.php line 168
Warning [PHP]: Unknown modifier '/' in file class/module.textsanitizer.php line 373
Warning [PHP]: Unknown modifier '/' in file class/module.textsanitizer.php line 373
Warning [PHP]: Unknown modifier '/' in file class/module.textsanitizer.php line 373
Warning [PHP]: Unknown modifier '/' in file class/module.textsanitizer.php line 373
Warning [PHP]: Unknown modifier '/' in file class/module.textsanitizer.php line 373
Warning [PHP]: Unknown modifier '/' in file class/module.textsanitizer.php line 373
Warning [PHP]: Unknown modifier '/' in file class/module.textsanitizer.php line 373
Warning [PHP]: Unknown modifier '/' in file class/module.textsanitizer.php line 373
Notice [PHP]: Undefined index: fromuid in file kernel/notification.php line 111

Hope this helps

nothing ?