Pike 7.6 detects that I have Java (-lzip -ljava -ljvm ), but 7.7 doesn't.
Checked out when? There's been some problems during the phasing in of the libffi bundle, but right now it seems that even though the bundle still does not work, you should be able to build without it at least.
The contents of modules/Java/config.log from your 7.7 and 7.6 build trees could be interresting as well.
pike-devel@lists.lysator.liu.se