This problem is not unique to me, unfortunately:
http://discussions.apple.com/thread....88370&tstart=0
But this may be a solution:
This may be a solution (
http://en.wikipedia.org/wiki/Sony_Reader) :
Mac OS X
Sony released an official Mac OS X client for the Reader with the release of the PRS-300 and PRS-600. It is reported to work with the PRS-505, PRS-700, Reader Pocket Edition and Reader Touch Edition.
The software works under 10.6 Snow Leopard, but only under 32 bit mode as it relies on a kernel module that does not currently support the optional 64 bit kernel.
I'll try it out and get back.