Tried with yum as per DAG's instructions, got:
[root]# yum search firefox
Repository base already added, not adding again
Searching Packages:
Setting up Repo: dag
repomd.xml 100% |=========================| 1.1 kB 00:00
Setting up Repo: base
repomd.xml 100% |=========================| 1.1 kB 00:00
Setting up Repo: updates-released
repomd.xml 100% |=========================| 951 B 00:00
Reading repository metadata in from local files
primary.xml.gz 100% |=========================| 1.4 MB 00:09
http://apt.sw.be/fedora/3/en/i386/da...rimary.xml.gz: [Errno -1] Metadata file does not match checksum
Trying other mirror.
Error: failure: repodata/primary.xml.gz from dag: [Errno 256] No more mirrors to try.
:-(