actionscript 's http post with underscore problem

when you write flex with http post with key=value,when key contains underscore ,then flex Urlvariable will convert it into %5f,the solution is Just change Urlvariable to string

 for example:

var url:String = "login_action.php";
					var request:URLRequest = new URLRequest(url);
					var variables:URLVariables = new URLVariables();	
					variables.user_name ='bob';
	
	request.data = variables 

to 

 

var url:String = "login_action.php";

var request:URLRequest = new URLRequest(url);

request.data = "user_name=bob";