I have an ASP.NET MVC 3 Web App, designed primarily for Mobile IE6 (WinMo 6.5 devices)
var lbType = '<%= HttpContext.Current.Session["myVar"] %>';
I can use it, display it in an alert, whatever... that works, no problem.
var lbData = '<%= HttpContext.Current.Session["myData"] %>';
var lbData = 'lots of data\r\nmore data\r\nmoredata\r\nmore data\r\n';
and it works fine. I can work with it, show it in an alert, whatever I need to do.
p.s. I have also successfully displayed the contents of the Session variable on the page by injecting it into the HTML (but that doesn't do me any good other than seeing it)