diff --git a/src/mongo/db/curop.cpp b/src/mongo/db/curop.cpp
index 2b74983..01d78ec 100644
--- a/src/mongo/db/curop.cpp
+++ b/src/mongo/db/curop.cpp
@@ -219,6 +219,7 @@ namespace mongo {
 
         if( a ) {
             b.append("secs_running", elapsedSeconds() );
+            b.append("msecs_running", elapsedMillis() );
         }
 
         b.append( "op" , opToString( _op ) );