On Mon, Mar 15, 2010 at 5:34 PM, Sergiu Dumitriu <sergiu(a)xwiki.com> wrote:
  Theoretically, this bug was fixed (see
 
http://jira.xwiki.org/jira/browse/XWIKI-299 ) by manually moving
 existing affected properties to the new correct type when a problematic
 class change occurs. Why does it continue to happen, beats me. I'll have
 to investigate again. 
Note that the bug probably was fixed. Earlier  Paul wrote:
  with our XWiki 1.5 I encounter the following complaint
at trying to 
save the document of a user, even after a restart of the servlet
container:
Sergiu -- Thank you for the very interesting explanation of what's going on
under the hood!
Definitely added to my bookmarks.
-- Niels.