Well, at least this bug appears even with only one user. I know nothing about how the page content is processed, but my idea is that the bug is caused by this data somehow (which is why I've been referring to the ghost in the code, not the heisenbug... I've been thinking of this one before, too). Maybe in conjunction with page ACLs. I'll check if removing the core pages "heals" the wiki again and if so, I'll try to determine which part of the core pages causes the effect.
I managed to get something *very* strange happening with the german corepages: after a few edits, it has become impossible to edit the Main page.
Not because of ACLs, but because request.getParameter() is returning the *page content without edits*. This should NOT be happening.
I'm also a bit suspicious of WikiPage.clone(), which isn't cloning attributes or acls. This could have some side effects somewhere. I'll be testing that...
/Janne
