problem with telnet to smtp port
 

Dear All,
i am facing an strange problem. i have configured iRedmail in CentOS 5.6. after installing that, i cannot telnet to gmail, hotmail and yahoo in smtp port. but i can do telnet to any other smtp server other than those 3. even i can receive mail from gmail, hotmail and yahoo. but cannot send mail. when i try to do telnet to those server i get "connection time out". i have checked RBL and reverse dns. everything is fine. can any one tell me , how to solve this problem?

Are you trying to do this:

If you are, I would expect gmail,yahoo,etc... to be blocking those connections for security purposes.