If the credentials contains characters like a single quote ('), double quote (") or backslash (\) then they were quoted. I don't know why they are quoted (maybe a default behavior of Joomla), but to avoid login problems we have to unquote them. Here is my solution:
I edited comprofiler.php at line 1206+1207 and changed it to:
Code:
$username = trim( stripslashes( cbGetParam( $_POST, 'username', '' ) ) );
$passwd2 = trim( stripslashes( cbGetParam( $_POST, 'passwd', '', _CB_ALLOWRAW ) ) );
Now i can login without problems.
Maybe this would help someone! ^^