10.1SP1 Transformations dialog box missing?

Hi all,

I need to add a bing basemap layer to a map i am building.
Before i usually opened a pre made map with bing basemap on it (WGS84 Web Mercator Auxiliary Sphere) and dragged it to my new map with the desired coordinate system (WGS 84 UTM ZONE 33S).
In the past a dialog box would open that allow me to transform between the two.
Now it just puts the basemap in the new map keeping its original system.

Any ideas?
Using 10.1 SP1