Applying changesets-latest.osm.bz2 to the database

Hello, I'm trying to update my open street map server. I'm building the server via the instructions at : http://weait.com/content/build-your-own-openstreetmap-server , however, in the comments section, it was noted that no one was able to update the database after it was built by following instructions at https://wiki.openstreetmap.org/wiki/Minutely_Mapnik . I'm a new-bee, so I'm assuming this can be done, but I need a pointer as to how to do this. Thanks Zak