diff --git a/README.md b/README.md
index cca5e41..950d82e 100644
--- a/README.md
+++ b/README.md
@@ -7,7 +7,7 @@ The module provides a single function to concatenate a list of JavaScript files
 
 ![Chrome Dev Tools screen shot](http://i.imgur.com/YPc20MJ.png)
 
-- Demo: http://jsbin.com/isozid/2/quiet
+- Demo: http://jsbin.com/isozid/3/quiet
 - npm: https://npmjs.org/package/concatenate-js
 
 ## When would you use it
diff --git a/concatenate.js b/concatenate.js
index 2438e42..8c88794 100644
--- a/concatenate.js
+++ b/concatenate.js
@@ -41,6 +41,10 @@ module.exports = function(files, opt_wrap) {
     var filename = sanitizeSingleLineComment(file.filename).replace(/^\//, '');
     var hostname = sanitizeSingleLineComment(file.hostname || 'app');
     var url = 'http://' + hostname + '/' + filename;
+    // //# is the new format. This was changed from //@ due to an
+    // incompatibility with IE conditional compilation. For now we support
+    // both.
+    content += '\n//# sourceURL=' + url;
     content += '\n//@ sourceURL=' + url;
     var js = 'eval(' + JSON.stringify(content) + ');\n';