James is much more battle-tested than most open source Java mail servers out there. This page was assembled to help give reasons to your boss on why James is a viable alternative.
Q: How long has James been running in production?
A: Since 1999
Q: How widely used is James?
A: In summer of 2003, we are averaging around 12,000 downloads per month. In summer of 2001, this was about 5,000 downloads per month. You can see the latest traffic stats here: http://www.apache.org/~vgritsenko/stats/projects/james.html
Q: How stable is James? On a suitable server does it crash once a week, month, or never?
(Kenny) I've been running my James install for about 5 months and I found it not running only one time. I don't know if it was James or badness on my server that caused it to die, but regardless, it's very stable.
(Danny) Less than once a month, I find it runs happily for 8 weeks or more and usually has to be restarted for reasons not directly related to stability. Reconfiguration is one example.
Vincenzo I agree, it's very very stable. I've had it running for about 4 months now, and I had only one problem causing an excessive cpu time, but the problem has been fixed.
(Mark) I've yet to have James crash on me. I have occasionally cycled it to add some new features, change config, move it to another server, etc... But i have never had James crash on me. So far, i've gone on average about 10 weeks between cycling it.
(Chris) In it's latest incarnations, I've not seen James crash once. My current install is 2.2.0a3, but that just went on line last Thursday. The previous version I used was 2.1.2a2 installed on 2/21/2003 and had no particular problems that I was aware of other than getting slow to respond when a spammer was deliberately trying to crash it.
(Guillermo) We use "james-3.0-trunk (nightly build 01.February.2007) + tuned patch" as relay&antispam, almost-non-stop without errors (only stops to make changes in configuration every 10 months approx), processing +20k emails/day.
It would be useful if above people would detail how many mailboxes (and messages per day) their setup supports. Running James successfully on a one mailbox setup or a 200 mailboxes one is different... Thanks
Q: How many messages can James handle before it experiences lag or buffer overload? Could it handle a T1 line with incoming messages?
A: Noel has run benchmarks of 600,000 (incoming) messages per day on an outdated 400Mhz Celeron running linux 2.2, and there is excess CPU remaining. He uses "postal", "rabid" and an SMTP sink, which can be found on the JamesRelatedTools page, to simulate a combined SMTP/POP3 environment.
Update: We have scalability test results at JamesByTheNumbers.
Q: Has anyone had any problem incorporating custom Mailets into the server or experienced any unusual problem with database connections?
A: Yes, it is difficult to add custom mailets. As of James v2.2 this is significantly easier. See CustomMailetPackages. Database connection pooling code is getting reworked and will not survive a database outage.
Q: Is there a published list of corporate users that anyone knows about?
A: We still start compiling a list here. Please feel free to add your name. In the meantime, the JamesUsers page collects comments from some existing users.
Q: Would you recommend James (version 2.1.3) as a production, scalable MTA?
A: Absolutely! James has great throughput capability, and we can assure you of its incredible flexibility and extensibility!
A: And we would recommend James v2.2.0 even more highly.
Q: Does james support mail filtering language: sieve?