when I run this code :

var howdyService:Service = new Service(
"http://localhost/flashservices/gateway",
new Log(),
"remoteServices",
null,
null );
var pc:PendingCall = howdyService.helloWorld();
pc.responder = new RelayResponder( this, "helloWorld_Result",
"helloWorld_Fault" );
function helloWorld_Result(result:ResultEvent)
.
.
.


the result is :
Service threw an exception during method invocation: No service named
remoteServices is known to Flash Remoting MX.

what is the problem because ?

thnx

That error I have found to be a mapping issue to your .cfc.

var howdyService:Service = new Service(
"http://localhost/flashservices/gateway",
new Log(),
"remoteServices",
null,
null );

This will be looking for remoteServices.cfc in your root directory.
Example IIS c:/inetpub/wwwroot/remoteService.cfc.

If your remoteService.cfc is in a subdirectory you would need to change
from "remotingServices" to "subdir.remotingServices".