We are having the same problem, but understood we cannot use the advanced edit.
So we create the signature, right click, add image, enter the image path and enter the hyperlink for one site. Is there a special way to enter two hyperlinks in this path to have it open both links when they click on it? With office 2007and above we can section out the hyperlinks, but we have several company sites still on office 2003. Any help is appriciated.