diff --git a/websocket-sharp/Server/WebSocketSessionManager.cs b/websocket-sharp/Server/WebSocketSessionManager.cs
index 88b3b291..e7dc0d19 100644
--- a/websocket-sharp/Server/WebSocketSessionManager.cs
+++ b/websocket-sharp/Server/WebSocketSessionManager.cs
@@ -98,9 +98,10 @@ namespace WebSocketSharp.Server
     /// </value>
     public IEnumerable<string> ActiveIDs {
       get {
-        foreach (var res in Broadping (WebSocketFrame.EmptyPingBytes, _waitTime))
+        foreach (var res in broadping (WebSocketFrame.EmptyPingBytes)) {
           if (res.Value)
             yield return res.Key;
+        }
       }
     }