Linux redhat7.1 smtp problem

I’m using Linux Redhat 7.1 KDE.I’m facing difficulties to enable my SMTP service.
When I tried to telnet 25 at the command prompt the message display
“Telnet:Unable to connect to remote host:connection refused”
It’s the same casefor http(80) and ftp(21) but there is no problem with Pop3(110).
I had even tried to used lokkit to enable the selected firewall option but the outcome still the
same.
Pls advise,these services is not running.