You may wish to read
this[
^] if you haven't seen it yet. It outlines some of the changes from version 2 to 3. The security model was redesigned to you may be affected by some of those changes. Included in your 3.0 downloads you should find some documentation outlining the differences between the versions. You may have to refactor some code to make it work. I personally don't use these systems, but I found answers with a handful of google searches.
Cheers.