Appearently in former versions 'serial' was used as key to

store history informations. In ZODB 2.8 'tid' is used.
At least the management screen is showing up again however
the 'description' value shows only garbage. Also there might a 
problem with backward compatibility.

lib/python/OFS/History.py

@@ -60,6 +60,7 @@ class Historian(Implicit):
     def __getitem__(self, key):
         self=self.aq_parent
 
+        print 'key', key
         serial=apply(pack, ('>HHHH',)+tuple(map(int, key.split('.'))))
 
         if serial == self._p_serial: return self
@@ -121,7 +122,7 @@ class Historical(ExtensionClass.Base):
 
         for d in r:
             d['time']=DateTime(d['time'])
-            d['key']='.'.join(map(str, unpack(">HHHH", d['serial'])))
+            d['key']='.'.join(map(str, unpack(">HHHH", d['tid'])))
 
         return r