I spent about half an hour or so upgrading the mailing list software I use. Spring [1] has a few issues with it—namely that she can't filter the email that it sends to her. I don't see what the actual problem is, since I do add several headers to each outgoing email (such as “List-Name:” which I added support for sometime in 2000) but her client (Microsoft's [DELETED-Lookout-DELETED] Outlook) can't sort on arbitrary headers. So she's been on my case to fix “that mailing list software I found on the side of the road” as she puts it.
Yes, the software is quite old. In checking I started using it back in 1995 (and even then it was a few years old) with version 1.0.0 (a search I just did revealed that version 1.2.0 was available in September of 1993 but I've yet to actually find a copy of the source code) with a few very minor modifications (that I've made) since.
But by the same token, the software is simple and I think there was only one real bug in the code which I fixed early on (what it was I don't remember—the comments only indicate I fixed something) and I haven't really had any problems since I started using it.
But I went ahead and played with it today. I added some code to add a tag to the subject line for easy filtering, which should make Spring (and some other users) happy.