So, I've learned my lesson. When I first set up this blog I said at great length that I'd prefer using Django's built-in commenting system than the third-party Disqus service that Mingus uses by default.
Well, after a week of trying to stop a flood of spam comments, first by deleting them as they came in and then by disabling comments altogether, I've taken the plunge and reverted my changes, so I'm now incorporating Disqus. All the (13!) real existing comments have been ported over to Disqus.
For those who are interested, copying the comments over was surprisingly simple. I thought I'd have to create some XML to import them into Disqus, but it turns out there is a nice API. It further turns out that the django-disqus app includes a simple management command,
disqus-export, which copies the comments straight over. One issue - the fork of this app included in Mingus has some issues with this command on recent Django versions, but you just need to remove the
verbosity option in the script to make it work.