How to send cyrillic data with indy10 Delphi

When I send Cyrillic text to a website, the text is displayed using "?????????" .... Here is my send function:

http := TIDHttp.Create(nil);
http.HandleRedirects := true;
http.ReadTimeout := 5000;
http.Request.ContentType:='multipart/form-data';
param:=TIdMultiPartFormDataStream.Create;
param.AddFormField('adtitle','  ');
param.AddFormField('area',' ');
http.Post('http://www.example.com/',param);