Use the following link to subscribe to the jfor mailing lists, hosted on SourceForge:
Select the appropriate list based on their descriptions and use the Subscribe/Unsubscribe/Preferences link.The archives of our mailing lists are in theory available on SourceForge as well, through the link above, but currenty (January 2003) they do not work anymore.
Fortunately the lists have been archived on GMane as well, and can be accessed from these links:
Here's an example of searching on GMane. You can click it to access the search page with the same search parameters: