needing the CD after installation for apt-get installs bugs me

[David Williamson]

Why do we need the CD to install some packages after initial
installation of Ubuntu, when the latest is always on the net?  Libranet
does this too, and it's absolutely infuriating <to me> to have to hunt
down the install CD only to find it's not used.  Is there a way to
change this behaviour?

example:

apt-get install mozilla-thunderbird
Reading Package Lists... Done
Building Dependency Tree... Done
Suggested packages:
  mozilla-thunderbird-offline mozilla-thunderbird-typeaheadfind
mozilla-thunderbird-inspector mozilla-thunderbird-enigmail
Recommended packages:
  xprt-xprintorg
The following NEW packages will be installed:
  mozilla-thunderbird
0 upgraded, 1 newly installed, 0 to remove and 2 not upgraded.
Need to get 0B/11.3MB of archives.
After unpacking 33.4MB of additional disk space will be used.
Media Change: Please insert the disc labeled
 'Ubuntu 4.10 _Warty Warthog_ - Preview i386 Binary-1 (20040929)'
in the drive '/cdrom/' and press enter

I suppose if what's on the CD is the same as what's available via apt it
might make sense, but since I've got fast internet, I can usually
install the app before I can find the CD ;-)

Thanks --

david williamson