In fact I think I reported uncorrectly the issue. The problem we are facing is that outside IE, the toolbar displayed in Firefox or Chrome is grey and is not showing the Menu button that allows to print Sheet in PDF. We are not using reports to do that since I did not understand how to do.
So regarding that aspect, we find some difficulties to correct bugs in IE 8 & 9 because some users where not having the right toolbar. Now we fix by installing the qvpluginsetup.exe. But he has to be done one by one for each individual. We still are looking for fiwing Firefox/Chrome issue.
If you can help it will be very helpfull.