Using templates from services with different themes

Hi,

I have two services x and y, one with theme 98 and the other with theme 99. I have set the ~sources parameter and service x cannot find templates on service y. The only way I can access them is if they are using the same theme (ej. 99).

Does anyone knows if is possible to access templates on services with different themes?

I was thinking calling service y from service x using Call Browser and service y URL but I can't get it to work.

Does anyone knows how can I call service y from service x when I press a button?

Thanks