I've tried with various Kyocera and Oki models, all with the same result.
Strange thing is, another web app that's using the same version (now, after I upgraded to SP6, it's better to say an older version) of the CrViewer but on another server has no problems.
If I'm not wrong, the Crystal Viewer uses the local printers drivers while printing, so I don't understand why one app prints correctly and another one does not.
I haven't tried to change the registry as suggested in the Microsoft article you mentioned, I will try it tomorrow morning at work.