Resource.Load() internationalisation issue/non english characters

Hi,

After upgrading to Unity5 I've run into an issue with non-english characters which worked fine previously. I'm loading assets at runtime which contain the Swedish letters ÅÄÖ as such:

 Resources.Load("Materials/Letters/letter_Ö",typeof(Material)) as Material;

This now fails unfortunately as the resource returned is null.

Anyone know a solution (or a workaround)?