How do I configure Sendmail to Queue when using SMART_HOST
I have a linux server sitting behind a firewall that makes it unable to send mail directly to the outside world. Instead it is configured to relay all mail through an approved smtp relay host. This works - except that sending mail is *really* slow - typically 30 - 40 secs per message.
The mails are sent from a CGI application, so this delay is not acceptable and I need another solution. I know I can change my application to workaround the problem, but I feel that sendmail should be able to handle my requirement.
What I'd like to do is have the sendmail running on my application server to accept the messages instantly and then hand them off to the smtp relay host as and when it can.
I've been reading the docs and surfing the web for a day now and seem no closer to finding a solution - yet this must be a common requirement and I must be missing something obvious.