CVS has an excellent feature with an annoying quirk about
it. CVS allows a module to include other modules, a feature
which GNOME uses to better organize things and to reduce
duplication of code. Unfortunately, the cvs
update command doesn't bother to check to see if any
new modules are included off of the main module. If you think
there is a missing piece, use cvs get
instead, it will check for new included modules. Don't worry,
as long as the source tree is there, it won't try to do a brand
new checkout, it will act the same as cvs
update as far as only downloading what is new or
updated.