[Zope] Tracker Export Problems

Hi, I have tried to export an existing tracker to a different zope. from zope v. 2.4.0 to 2.5.1 When i try to import it, i always get the error no module named splitter. I also tried to export the whole content of the zope by copying the Data.fs file: I can view the Tracker postings , but if i want to edit the state of a message i get the error: attribute error: split If anybody knows how to get the stuff working, please respond. thanx, Sebastian