[CentOS] centos5 - yum groupinstall and yum grouplist

If I do a minimal centos 5 install

Then if I do a

yum -y update

then if I do a 

yum groupinstall "Development Tools" "Development Libraries"

(is that syntax right, it works)?

both are installed yet if I 

yum grouplist

this is all that shows up as installed even though both are installed

Installed Groups:
   Development Libraries
   System Tools
   Dialup Networking Support
   Network Servers
   Mail Server

If I check to see if I can install them individually after that they both
say there are installed and up to date.

:-)

Just wondering if it was something that needs to be addressed as a minor
inconvenience or pretty output type bug

thanks

--
Abba Communications
Spokane, WA
www.abbacomm.net