Reiserfsprogs is apparently part of an emerge system and in the build docs it says to emerge reiserfsprogs. If emerge system completes it's already installed. Now I use ext3 and would prefer it not be included in "system". That way I could sucessfully unmerge it and it would not want to reinstall when I do emerge -u system.
reiserfsprogs has been removed in the lastest system thus all your issues have been taken care of :)