PMDF Installation Guide
 OpenVMS Edition
1.7.2 Additional Post-Installation Tasks for Sites Upgrading from PMDF V5.2  or Earlier
  - The format of the PMDF queue cache database has changed (storage 
  efficiency has been improved) since PMDF V5.2. It you are upgrading 
  from PMDF V5.2 or earlier, you must rebuild your queue cache database 
  using this command:
   - As Web500 is no longer provided, you should remove any WEB500 service  definition from your 
dispatcher.cnf
 file and any  WEB500 path definition from  your http.cnf
 file.