I made my workbench using this technique and white oak. I do not think I used any glue - it is a very, very strong joint and the strength comes from the bend in the dowel. You could add a little glue if you wanted to, but I do not think it is necessary. The joint actually just ensures the mortise and tenon stays together which you are presumably going to glue. Hope you will post some pics when it is complete....I would love to see them.
Scot