I have a strange problem with a couple of my users who connect to an FTP server running on FreeBSD 8.1 (the server is PureFTP). Other users (whose workstations are on the same LAN as the problematic ones) use this server with no issues. But these two in particular are unable to connect to the server at first. Whenever they notify me that they can't connect, I will come over and ping the server from their workstation. The ping will work, then all of a sudden they can connect to the FTP server without issue. Any ideas why this might be happening?