[Zope] problem moving ZODB to new Z

Hi Zopesters, We have just migrated from a machine running Zope with the ZServer to a different machine running Zope with an Apache web server. But we have a problem, namely, after copying over the Data.fs ZODB to the new site, Zope cannot find a needed (but installed) product (Navigator). This product definitely exists: /Zope-2.1.0-src/lib/python/Products/Navigator so why is Zope not seeing it? i

From the manager view of the ZODB:

Product at /optics / Control_Panel / Products / Navigator There are currently no items in Installed product Navigator (Navigator Product, Version 1.02) Any help is much appreciated as my site is off-line until I can fix this problem. Cheers, Darran.