I am trying to reply to a comment and the page hangs at this url http://homegrown.org/blog/wp-comments-post.php with a blank screen. I've just updated from 3.4 to 3.4.2 and am still having the problem. I've tried replying from the WP dashboard as well and that doesn't work either. I type the text in the comment box, the circle makes one cycle, but then the text remains in the field with no comment.
We do use a custom theme.