The Windows installer for 5.0pre1 (daily build) doesn't create the "keymaps" folder.
Invoking jEdit (with empty settings directory) gets an "Fatal error": "System keymap folder do not exist, your installation is broken. Install keymaps in %JEDIT_HOME%\keymaps". After confirming the dialog, jEdit quits.
I didn't see the bug item so I forgot to add it in the svn commit, but it was fixed in rev 21564
It is not in CHANGES.txt because it was only a regression in 5.0