Rogue spaces in settings causes failed authenication

I'm running a half dozen drupal sites with LDAP. One new one I set up was having problems authenticating users. I was just about to toss the site since I had already setup a replacement version which was working when I saw a post with similar symptoms. I had assumed the failed login was caused by some additional complications with our setup. Instead of tossing it, I kept tracking the problem in case it was the same as the post I saw - very similar in that there were no ldap errors, only a "Login attempt failed" error.

So I tracked my problem back to a space at the end of the uid setting - so instead of sAMAccountName I had sAMAccountName  on the server settings page. Notice the extra space? This is passed to AD as part of the filtering. I'm not sure if other rogue spaces will cause similar problems, but you should check all of your settings for such a rogue space if you are having inexplicable authentication problems.

I'll patch HEAD next time I do an update to strip white spaces from any settings.