--- a/dbapi.py	Wed Mar 03 18:31:08 2010 +0100
+++ b/dbapi.py	Wed Mar 03 18:32:21 2010 +0100
@@ -398,14 +398,20 @@
 
     def check(self):
         """raise `BadSessionId` if the connection is no more valid"""
+        if self._closed is not None:
+            raise ProgrammingError('Closed connection')
         self._repo.check_session(self.sessionid)
 
     def set_session_props(self, **props):
         """raise `BadSessionId` if the connection is no more valid"""
+        if self._closed is not None:
+            raise ProgrammingError('Closed connection')
         self._repo.set_session_props(self.sessionid, props)
 
     def get_shared_data(self, key, default=None, pop=False):
         """return value associated to `key` in shared data"""
+        if self._closed is not None:
+            raise ProgrammingError('Closed connection')
         return self._repo.get_shared_data(self.sessionid, key, default, pop)
 
     def set_shared_data(self, key, value, querydata=False):
@@ -416,6 +422,8 @@
         transaction, and won't be available through the connexion, only on the
         repository side.
         """
+        if self._closed is not None:
+            raise ProgrammingError('Closed connection')
         return self._repo.set_shared_data(self.sessionid, key, value, querydata)
 
     def get_schema(self):
@@ -501,6 +509,8 @@
     def user(self, req=None, props=None):
         """return the User object associated to this connection"""
         # cnx validity is checked by the call to .user_info
+        if self._closed is not None:
+            raise ProgrammingError('Closed connection')
         eid, login, groups, properties = self._repo.user_info(self.sessionid,
                                                               props)
         if req is None:
@@ -521,6 +531,8 @@
                 pass
 
     def describe(self, eid):
+        if self._closed is not None:
+            raise ProgrammingError('Closed connection')
         return self._repo.describe(self.sessionid, eid)
 
     def close(self):
@@ -535,6 +547,7 @@
         if self._closed:
             raise ProgrammingError('Connection is already closed')
         self._repo.close(self.sessionid)
+        del self._repo # necessary for proper garbage collection
         self._closed = 1
 
     def commit(self):