Be sure to clear the original cache when calling resetCache().

XXX I've got no idea what this is actually supposed to do.  It may be
that clearing the old cache isn't safe, but only if it never was.  If
a non-ghost object is in the cache, it seems that attempts to use it
will go through the wrong cache.

src/ZODB/Connection.py

@@ -13,7 +13,7 @@
 ##############################################################################
 """Database connection support
 
-$Id: Connection.py,v 1.90 2003/04/23 20:05:51 jeremy Exp $"""
+$Id: Connection.py,v 1.91 2003/04/23 20:36:02 jeremy Exp $"""
 
 from __future__ import nested_scopes
 
@@ -252,6 +252,7 @@ class Connection(ExportImport.ExportImport):
         self._code_timestamp = global_code_timestamp
         self._invalidated.clear()
         orig_cache = self._cache
+        orig_cache.clear()
         self._cache = cache = PickleCache(self, orig_cache.cache_size)
         self._incrgc = self.cacheGC = cache.incrgc