Yes, it can be done. In the materials lab, hit the Image Texture button (labeled "P" for some odd reason) to use a picture texture. Then go into the Texture source editor. Load the standard texture into the first window, then the bump you want to use in the second window. Hit the check mark and it puts you back into the material editor. Set the bump to the texture A value, and set the value to about fifty for starters.... Exit the materials lab and see if it's bumpy enough for you. You may have to play with the number value to get the result you want (the number may be either positive or negitive, BTW). Good luck!