diff --git a/db/dbcommands.cpp b/db/dbcommands.cpp
index f6ed7c68776..1312927467d 100644
--- a/db/dbcommands.cpp
+++ b/db/dbcommands.cpp
@@ -1505,14 +1505,13 @@ namespace mongo {
             }
 
             assert( size <= 0x7fffffff );
-            BSONObjBuilder b( (int) size );
-            int n=0;
+            
+            BSONArrayBuilder b( result.subarrayStart( "values" ) );
             for ( set<BSONElement,BSONElementCmpWithoutField>::iterator i = map.begin() ; i != map.end(); i++ ){
-                b.appendAs( *i , b.numStr( n++ ).c_str() );
+                b.append( *i );
             }
-
-            result.appendArray( "values" , b.obj() );
-
+            b.done();
+            
             return true;
         }
 
diff --git a/db/jsobj.h b/db/jsobj.h
index e4cc9f2915c..709c6451101 100644
--- a/db/jsobj.h
+++ b/db/jsobj.h
@@ -1662,7 +1662,7 @@ namespace mongo {
         }
 
         BSONArrayBuilder& append(const BSONElement& e){
-            _b.appendAs(e, num().c_str());
+            _b.appendAs(e, num());
             return *this;
         }