Closes #12734 Thanks @paulguy for the fix!
In some non-standard implementations, the server may respond AUTH_USER_PASS even if's not listed in available authentication methods. (it should respond AUTH_NO_ACCEPTABLE per standards)
Fixes #12482
Thanks to @makgun02 Ref: http://pastebin.com/raw/JX9gHFUz
The previous fix for #5594 is incorrect