This is a common problem with both internal and third-party applications. It is becomming a criticial issue, as Microsoft has de-supported MSJVM and companies have to migrate to Sun JRE. For third-party applications, it is particularly tricky from a patch/update deployment issue, as many web-based applications are not clearly documented and users do not understand that it won’t work until after deploying the update. In our case, we remove all prior versions of the JRE and lay down the current version. My recommendation is to NOT design an app to check for a specific version – which is the root cause of the problem. But even if you do this, you have to retest every application against the new release before giving approval for general deployment.