This is very promising. Ever since Gmail for domains and Outlook for domains became paid-only, I've been looking for alternatives. This looks like potentially a perfect solution.
You might want to look into roundcube [1] which is another PHP webmail application that has a very nice UI,, (more) mature codebase, and is on an (arguably) better license (GPL3). I can't say how it compares to rainloop because the demo servers are slammed right now, but I would recommend roundcube in general.
Doesn't make sense because Squirrelmail is also written in PHP and it's pretty solid. The next version will use HTTP-only cookies to further harden against attacks.
do you know of any particular reason that wasn't put in to place years ago? concern for legacy browsers at all costs? it sounds snarky, but it's a genuine question - I think I've set my apps to be http-only cookies for a while now, and am wondering why someone would only get around to it in 2014.
