Making a search from the index page is no problem.
However, making a search while viewing a post results in 'Error: please type a comment.'
The resulting URL is http://domain.com/wp-comments-post.php
I've tried updating wp-comments-post.php, and I've also read other complaints which seem to point to a difference between URIs in WordPress Address and Blog Address but mine has the same values.
I've disabled my .htaccess file but no change.