I am having the same problem. I don't run sendmail but my proftpd service takes a long time to connect as well. After connection is established, the service runs normally. I don't run a firewall. I run proftpd as a standalone FTP daemon. Here's a log from a client with timestamps:
Code:
[11:25:29] Connected to 192.168.0.102 Port 21
[11:26:19] Ident Request: 192.168.0.102
[11:26:19] 220-unauthorized access is not permitted.
[11:26:19] 220 (server is masked)
[11:26:19] USER drew
[11:26:19] 331 Password required for drew.
[11:26:19] PASS (hidden)
[11:27:39] 230 Access granted for drew.
[11:27:39] SYST
[11:27:39] 215 UNIX Type: L8
[11:27:39] REST 100
[11:27:39] 501 REST not compatible with server configuration
[11:27:39] This site may not allow file resuming
[11:27:39] PWD
[11:27:39] 257 "/" is current directory.
[11:27:39] TYPE A
[11:27:39] 200 Type set to A.
[11:27:39] PASV
[11:27:39] 227 Entering Passive Mode (192,168,0,102,11,194).
[11:27:40] LIST -al
[11:27:40] 150 Opening ASCII mode data connection for file list
[11:27:40] 226 Transfer complete.
[11:28:26] QUIT
[11:28:26] 221