I have noticed this problem a lot of websites, however i haven’t had any problems with my wordpress installation…
Perhaps its some plugins that cause the blank page to appear… Or then again perhaps the theme that you’ve installed modified something in comment posting… be sure to check if its some spam comment filtering plugin that stops bots in their way that is reacting by putting out a blank page or it is the theme…
Try removing all or installing some new things… If i get the problem on my blog later on and i resolve it, i will let you know…
Hope this helps…
