I did my best to search the forum, but was unable to find a note on this issue. If it has already been discussed, I apologize in advance.
I am using WinSCP 4.0.7 in Explorer mode. When I connect to a server via SFTP with tunneling, it works like a charm. If I add another session that uses SFTP to connect server not using tunneling, both sessions work fine. Now, if in place of the second session not using tunneling, I open an SFTP session with tunneling, WinSCP asks me to accept a key. After that, everything goes bonkers. The first session works fine, however, the second session either starts to work properly, then stops OR the second session acts like it's connected to the correct server, but in reality, it's connected the the first server. This happens if I go through the same tunnel server, or different tunnel servers.
Other than that, I continue to enjoy this project. WinSCP has made my life much easier... especially with tunneling.