Bing maps problem in Outlook client since CRM 2015 Update 1 (Online)

We are getting an error : "VEMap is undefined" when we open a form which has a web resource that calls the Bing maps REST api.

This is the script we are loading -

http://ecn.dev.virtualearth.net/mapcontrol/mapcontrol.ashx?v=6.2

and this is the line that has the error -

var map = new VEMap("map");

This only happens from inside Outlook, it works fine on the web. It has only started happening since Update 1.

Any ideas why this may be?