diff -r b758351d191f -r cc9b7e14412b web/lib/django/db/models/aggregates.py
--- a/web/lib/django/db/models/aggregates.py	Wed May 19 17:43:59 2010 +0200
+++ b/web/lib/django/db/models/aggregates.py	Tue May 25 02:43:45 2010 +0200
@@ -43,9 +43,6 @@
         """
         klass = getattr(query.aggregates_module, self.name)
         aggregate = klass(col, source=source, is_summary=is_summary, **self.extra)
-        # Validate that the backend has a fully supported, correct
-        # implementation of this aggregate
-        query.connection.ops.check_aggregate_support(aggregate)
         query.aggregates[alias] = aggregate
 
 class Avg(Aggregate):