According to the faq, it states that there is a problem with the rpm database after a 5.x to 5.1.2 upgrade. It states that you should boot into single user mode and run the command rpm --rebuilddb. This error also happens after a fresh install of 5.1.2. When you boot into single user mode and execute the following command rpm --rebuilddb, you get a command not found error. performing a find / -name rpm returns no files found. The installs I performed were SERVER ONLY. My guess is that those who have performed the server/gateway installs have not had this problem.