I finally got around to adding permanent link functionality to my template. I don't know why it took so long to add it, but there you are. Anyway it occured to me that mine aren't really permanent links in the true sense of the term, due to the fact that I'm using web forwarding to manage my domain name. All of my permanent links make reference to the IP address of the server the site is hosted on, as the domain name is managed by a company in the UK (which is also why the whole site is actually shown inside a huge semi-invisible frameset).
So anyway, permanent links are now available, but if I move servers then they're all going to break :)