If you want to read more on the subject of Rodinal, you might be interested in this post on rec.photo.darkroom, in which Michael Gudziniwicz discusses someone else's "home brew" made with p-aminiphenol:


You can see the whole thread by clicking on the link of the title , i.e. "My Home Brew."

Unfortunately rec.photo.darkroom isn't nearly as good as it used to be, but there are some gems there.