diff --git a/Event/EventInfo/test/MergedEventInfo_test.cxx b/Event/EventInfo/test/MergedEventInfo_test.cxx
index f201a41b79da4cc59093ff3e1e0f85ce2513d117..a06609b573c816a49a550f6fbbfcfee5482afa10 100755
--- a/Event/EventInfo/test/MergedEventInfo_test.cxx
+++ b/Event/EventInfo/test/MergedEventInfo_test.cxx
@@ -15,7 +15,8 @@ using namespace std;
 int main() {
   cout << "*** MergedEventInfo_test starts ***" << endl;
   MergedEventInfo empty;
-  assert( static_cast<EventID::number_type>(-1) == empty.event_ID()->run_number() );
+  assert( static_cast<EventID::number_type>(-1) == empty.event_ID()->run_number() || // Gaudi 27
+          0 == empty.event_ID()->run_number()); // Gaudi 26
   EventInfo anInfo(new EventID(1, 23), new EventType(), new TriggerInfo());
 
   MergedEventInfo merged(anInfo, 3, 33);