Parsing Date from webservice

var date = new Date(1310187160270+1200); 
console.log(date)

returns

Sat Jul 09 2011 06:52:41 GMT+0200 (South Africa Standard Time)

If you need to strip it as is in Question:

var returnVariable = "/Date(1346713200000+0100)/";
var d = new Date(parseFloat(returnVariable.replace("/Date(", "").replace(")/", "")));