I just found out something else.
Maybe it was ocred after all. because I just scanned some random textpage of a magazine and it did not do the auto recognition thing I encounter with this pdf.
What is differnent about this pdf compared with all others is:
1) it is about 10 times larger in MB
2) if you open the pdf in windows using adobe reader, and you go to document properties, you can choose the "fonts" tab.
In every pdf it contains a list of fonts with next to them "enclosed" or "enclosed subset"
(:edit I think the right word is embedded ,not enclosed <==I translated it from my not english version
)
In this particular pdf that gives the blocks iso the text or nothing at all using the other reader, it also has a whole list of fonts, but none of them has the above text next to it.
All fonts seem to be true type fonts.
This leads me to believe that since the fonts do not come with the pdg, it will look for the fonts on the local system. maybe my desktop windows and desktop linux have those fonts and the ereader doesn't?