Acmlmboard copyright/license

I was just pondering things today, when I realized that none of the mainline Acmlmboards have any real license...or any license at all for that matter (ABXD does have a BSD license, but that's about all.) Neither the 0.X, 1.X, nor 2.X branches have any license, and it isn't clear as to what exactly you can do with the software, or how you can modify and distribute it.

My Acmlmboard 0.7 fork (which I've been farting around with on-and-off for a few years now; still need to make more releases available) is part 2000's Acmlm code and mostly my rewritten code. However, I've peaked at 1.92 and Acmlmboard II's source and database a bit to see how certain things are done and taken influence from them (and copied the poll SQL tables from 1.92, which I never ended up implementing, along a few schemes and layout PHP snippets)

I'm eventually going to add a credits.php page listing all my inspirations, whether SQL tidbits, peeking at PHP, or PHP snippets.

So here's what I want confirmation on: since code contained within my fork (or any other mainline fork) is copyrighted by others and under no license, it's not possible to release my fork as free software, only as "freeware" (with the respective copyright notices included.)

Edit: I created an example "nonlicense" for my forum software in my other thread.

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