[zerospinboson]

ever since i got my iLiad i've been reading a newspaper with it, and while it works reasonably well, the feature i'm really missing is a 'back' button for the iPDF viewer..
as you might imagine, the newspaper (a PDF) is set up in such a way that it first has about 20 pages with the links and short introductions to the articles themselves, and the actual articles are appended to it..
Which is all well and good (you can click the links with the stylus and go there fairly reliably).. but after you've read the article the only way you can return to the index is by clicking one of the links in the top frame of the pdf, and that returns you to the first page of whichever part of the paper you clicked to view.
Most parts have more than 1 page worth of 'indexed' links+article heads, though, and having to return to the first page of the index is fairly annoying, so i was wondering if it was possible to define some sort of back button/feature in either the main viewer or a replacement one.

does anyone have a clue as to how doable it is to implement this?
thanks in advance