title: SPContext.Current.Web.CurrentUser is null
body: <p>I have created site (http://spf2010/mysite/ for example) and WCF Service, which is hosted in ISAPI folder.
  I have silverlight web-part and python script which connect to this service using the same address <a href="http://spf2010/mysite/_vti_bin/MyService.svc/mex" rel="nofollow">http://spf2010/mysite/_vti_bin/MyService.svc/mex</a>
  In case when silverlight web-part connects to WCF-service it's ok, but when python script connects, then SPContext.Current.Web.CurrentUser object is null.</p>
  
  <p>By the way, if I start project under debug mode in Visual Studio CurrentUser object is correct even if python script calls web-service.</p>