Qmail woes
I wouldn't recommend anyone ever to use qmail, no matter how beautiful the architecture might strike you. It's confusing, takes a solid two hours to even find a document to read, and there doesn't at all seem to be much community support for it. Most of the time you're left to your own devises with a--excuse my saying so--retarded mail server.
Maybe you know about Transport Layer Security, or TLS for short. It's a common enough thing, SMTP servers are known for their use of TLS. Well, Qmail probably isn't, because the only TLS support there is is a huge patch whose website is presently down.
As it turns out, one of these days my TLS support had just given up. Qmail doesn't tell you though, oh no -- not at all. You have to dump the I/O it does with Gmail to know anything is going wrong.
If I were you, and I was using Qmail with TLS support (like I do), then I'd check if my SMTP server goes wonky after I send STARTTLS. Mine did, and didn't tell me.
Why does this matter? Well, as it turns out, Gmail doesn't deliver messages when TLS fails like this, and I can't really blame them because my server advertised support for TLS.
So in short: stay away from Qmail, don't accept patches from strangers and don't wake up too late.
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