New Post: Add new lookup item on the fly

genius,  I like your solution of saving the form in a hidden iframe.  For sessionStorage, I prefer to save the fields in a jQuery object array like so:

http://sharepointjavascript.wordpress.com/2010/04/07/revised-function-init_fields/

That way you can refer to the fields like this:  var titleFieldTR = $(fields['Title']);

Web storage is supported in Internet Explorer 8+, Firefox, Opera, Chrome, and Safari.

Can't say what's wrong, but you can Try it out here:

http://www.w3schools.com/html/html5_webstorage.asp

MS documentation:

http://msdn.microsoft.com/en-us/library/cc197062(v=VS.85).aspx

HTH,

Josh