I know it's your rules and all, but I'd like to say I would definitely be up for this jam (and even have an Infocom-related game in progress currently bound for IFComp that I'd probably submit here instead) - if it weren't for the requirement for games to be in I6 or ZIL. You could limit it to parser games and everything would still be in the Infocom spirit. I think the ZIL revival is a great thing but I just haven't got the time or spoons to learn a new language. I suspect there are a lot of authors in I7 and possibly Dialogue (which compiles to Z-code)  as well.

But again, your jam, your rules. I hope it goes well.

I was also interested in joining, but haven't done so for a completely different reason.

I've only played half a dozen Infocom games and that was almost 40 years ago. If memory serves me correctly, I've played (and finished) Zork 1, 2 & 3, Infidel, Planetfall & Hitchhiker's Guide to the Galaxy and played (but not finished) one or two others. The truth of the matter is that I'm really rusty on all things Infocom and I came up blank when it came to game ideas. I know, I know, it only has to have a vague connection to an Infocom game, but I'm currently working on a small adventure for another game jam and didn't have time to refresh my memory or do the research. The other game jam finishes on 7 July, so there's still time to prepare something for this jam if I feel inspired. I can whip something up pretty quickly in Inform 6.

Well, I would support including Inform 7 (IIUC, Inform 7 converts into inform 6 when compiling).  Though personally, I never liked Inform 7 when I took a look at it (admittedly, only briefly).  It felt odd for it to be in between a traditional programming language and English - kind of an uncanny valley for languages.  Anyway, I hope you two will be able to submit something, and good luck on your other jam, Garry.