I'm getting a really odd sftp problem -- if I sftp to my Mac via either unix sftp or some commercial sftp client from an outside service, I can connect to my server (login and password work fine), but upon listing the directory ("ls") it stalls out (nothing ever happens) and eventually disconnects due to the stall. Here's the weird part now: if I "sftp localhost", use my login and password, I can use ls with no problem. My firewall is open properly, but the stall only occurs from outside IPs.
I should note that I am on Earthlink, so my "internal" (router assigned IP) is not the same as my external IP -- could this be causing the problem? If so, how do I fix it?