I am not an email guru, but this might help: http://serverfault.com/questions/42519/h...ess-denied
If not: Google: centos sendmail: Cannot open mail:25 sendmail: RCPT TO:<*****@gmail.com> (454 4.7.1 <*****@gmail.com>: Relay access denied)
If not: Google: centos sendmail: Cannot open mail:25 sendmail: RCPT TO:<*****@gmail.com> (454 4.7.1 <*****@gmail.com>: Relay access denied)