Ok, many thanks to everybody.
So M92 works enough with wolfram alpha mobile web site.
By a post in Jetbook forum, it seems that the compatibility issue concerns the compatibility with SVG files, that web site in his full version uses for the image.
In fact, it seems also the problem Dulin's Books showed.
So the question could be if it is possible to install another browser to increase the compatibility.
Finally, a question that regards wifi: can the ereader connect also where signal is not so good (related to other kind of device, as notebook, smartphone. etc.) ?
Thank you for your reply.
Last edited by pizzikoku; 03-18-2012 at 07:07 AM.