Updating with yum - strange warnings about useradd

  Updating  : monotone                     ######################### [1/4]
Usage: useradd [options] LOGIN

Options:
  -b, --base-dir BASE_DIR       base directory for the new user account
                                home directory
  -c, --comment COMMENT         set the GECOS field for the new user account
  -d, --home-dir HOME_DIR       home directory for the new user account
  -D, --defaults                print or save modified default useradd
                                configuration
  -e, --expiredate EXPIRE_DATE  set account expiration date to EXPIRE_DATE
  -f, --inactive INACTIVE       set password inactive after expiration
                                to INACTIVE
  -g, --gid GROUP               force use GROUP for the new user account
  -G, --groups GROUPS           list of supplementary groups for the new
                                user account
  -h, --help                    display this help message and exit
  -k, --skel SKEL_DIR           specify an alternative skel directory
  -K, --key KEY=VALUE           overrides /etc/login.defs defaults
  -m, --create-home             create home directory for the new user
                                account
  -l,                       do not add user to lastlog database file
  -M,                       do not create user's home directory(overrides /etc/login.defs)
  -r,                       create system account
  -o, --non-unique              allow create user with duplicate
                                (non-unique) UID
  -p, --password PASSWORD       use encrypted password for the new user
                                account
  -s, --shell SHELL             the login shell for the new user account
  -u, --uid UID                 force use the UID for the new user account

  Updating  : monotone-server              ########################  [2/4]warning: user monotone does not exist - using root
  Updating  : monotone-server              ########################  [2/4]warning: user monotone does not exist - using root

Keeping my Fedora system updated is easy enough with yum, but lately I've noticed a couple of similar warnings, like this one above.

The messages warning: user monotone does not exist - using root does leave me a little puzzled, since it's a warning it shouldn't be a problem but since a user account is missing will it run correctly, does it use another account, is it just a bad RPM build/configuration or the worst possiblity something/someone has silently messed up my system!.

I've search for an answer on the web, but didn't really find one. Most posts were related to people trying to run src.rpm's or specific packages (where I think the problem is a bit more general). Anyway I've removed Monotone since I don't need it (I didn't even know that it existed). Leaving me with the ol' question of how to keep my system at the minimal without using endless time using yum and understanding what the different packages do , being just an average Fedora user I'm relaying primarily on default configurations