Would like to see this applied to SVN so I dont have to patch my installs in the future:
-failregex = ^%(__prefix_line)s(?:error: PAM: )?Authentication failure for .* from <HOST>\s*$
+failregex = ^%(__prefix_line)s(?:error: PAM: )?[A|a]uthentication failure for .* from <HOST>\s*$