I just downloaded a bunch of updates from one of RH's mirrors and attempted to install them via rpm -Uvh. Got the following results: installing package apache-1.3.9-8 needs 148Kb on the /home filesystem installing package apache-manual-1.3.9-8 needs 145Kb on the /home filesystem installing package ee-0.3.11-1 needs 145Kb on the /home filesystem installing package esound-0.2.17-1 needs 145Kb on the /home filesystem installing package esound-devel-0.2.17-1 needs 145Kb on the /home filesystem installing package groff-1.15-1 needs 145Kb on the /home filesystem installing package groff-gxditview-1.15-1 needs 145Kb on the /home filesystem installing package libtiff-3.5.4-1 needs 145Kb on the /home filesystem installing package libtiff-devel-3.5.4-1 needs 145Kb on the /home filesystem installing package linuxconf-1.16r10-2 needs 145Kb on the /home filesystem installing package linuxconf-devel-1.16r10-2 needs 145Kb on the /home filesystem installing package sharutils-4.2.1-1.6.1 needs 145Kb on the /home filesystem Now, at least one of the apache packages should have failed, because my /home is controlled by the automounter and NIS and thus unavailable. However, none of the rest of the packages require /home. If I issue the same command but omit the apache packages, the upgrade completes successfully. (Well, minus that annoying 'package README not found in file index', of course.)
This is correct behaviour. If you want to stop RPM from trying to use /home instead of indicating an error, you can use the --excludepath option.