You need to back up the Universal Password for all users before a major upgrade.
I created a cross platform (Java) Universal Password retrieval utility. You can download the zip file here.
In the zip file, dumpUP.bat is the batch file to kick off the process. You need to pass the application a few parameters:
My current command line is as follows:
192.168.0.1 636 cn=admin,o=admin password o=meta "C:\\Program Files\\Java\\jre1.5.0_07\\lib\\security\\cacerts"
Run the batch file and watch all users and passwords end up in the output file.