Recently I received a request from Jeremy, a MyPopchecker user, to allow MyPopchecker accounts to specify custom ports. This is useful if you have an SMTP or POP3 server running on a non-standard port.
Initially I thought, "Hey, sure, no problem." Programatically the only challenge is adding the database field and tweaking the socket code.
The more difficult part of this, as I came to discover, is that that some ISPs (like gmail) require SSL. Adding this functionality was a bit more of a roadblock, but it is important.
For the last year, MyPopchecker has supported SSL via a webserver certificate. This means that all communication from your browser to the webserver is secure, but backend communication is not secure. This is actually a weakness on the ISPs side, as most mail servers do not support SSL (or, are not configured to support SSL).
I think it's a great move on gmail's part to require this level of security. And now, I've integrated SSL into MyPopchecker -- so if your ISP supports SSL, use it! It will make all of your e-mail 100% secure. You can also specify any port you wish (regardless of whether or not you use SSL).
One additional challenge that I'll be working on is getting SMTP to work a bit "cleaner." In the good ol' days, most SMTP servers were open relays. Today, however, many SMTP servers reject mail if it is not originating from its own subnet, or within a network range. If you've ever tried to send e-mail from a friend's house or while on the road and had problems sending, this is probably why.
The problem is there is no single solution used across the board. Some reject e-mail outright if it originates outside an IP range, some SMTP servers require a username and password, some require SSL. What's worse is that often times, ISPs don't tell you this information, so it's a lot of trial-and-error to figure out what works.
My intent right now is to help clean up this process with how MyPopchecker sends e-mail. The good news is most of the time this works fine -- and if doesn't, MyPopchecker will tell you, so your e-mail won't be lost in limbo.