Mail not sending Gmail messages

Hello everyone,
I have tried to my best to figure out why my mail program will no longer send my GMAIL messages. It receives mail perfectly and used to allow me to send as well but about a week ago it stopped allowing me to send, when I try this is what it says:
The connection to the server “smtp.gmail.com” on port 25 timed out.

Select a different outgoing mail server from the list below or click Try Later to leave the message in your Outbox until it can be delivered.

and my available list to choose from only says this:
smtp.gmail.com (offline)


Any help would be greatly appreciated!

What I usually do is, login through webmail, then once i have done that, my Mail starts working again.

This is not working.

That's the wrong port for one... take a look at this help and it should get you up and going again: https://mail.google.com/support/bin/answer.py?hl=en&answer=13287

where can we set the port for Outgoing Mail server only? All I see in the preference > Advanced is 'Port' which is set to 995. If Incoming mail needs 995 as port then where do I set the outgoing mail server?

The link for Google Mail is informative but is not helping in addressing this issue.

This link is Apple Mail 2.0. I am using Apple Mail 3.4 which don't have an option as 'Server Settings' for Outgoing Mails.

Under the accounts setting click on the "Outgoing Mail server" dropdown list and then select "edit server list".

Then click "advanced" and enter the server port.