diff --git a/websocket-sharp/Net/HttpUtility.cs b/websocket-sharp/Net/HttpUtility.cs
index 3e3c78cf..55728fe6 100644
--- a/websocket-sharp/Net/HttpUtility.cs
+++ b/websocket-sharp/Net/HttpUtility.cs
@@ -612,11 +612,12 @@ namespace WebSocketSharp.Net
 
     internal static Encoding GetEncoding (string contentType)
     {
-      var parts = contentType.Split (';');
-      foreach (var p in parts) {
-        var part = p.Trim ();
-        if (part.StartsWith ("charset", StringComparison.OrdinalIgnoreCase))
-          return Encoding.GetEncoding (part.GetValue ('=', true));
+      foreach (var elm in contentType.Split (';')) {
+        var part = elm.Trim ();
+        if (part.IndexOf ("charset", StringComparison.OrdinalIgnoreCase) != 0)
+          continue;
+
+        return Encoding.GetEncoding (part.GetValue ('=', true));
       }
 
       return null;