root@zeus [/etc]#  up2date --whatprovides=lsof
lsof-4.63-4.1
root@zeus [/etc]# apt-get install 
root@zeus [/etc]# up2date -i lsof-4.63-4.1

Fetching Obsoletes list for channel: rhel-i386-es-3...

Fetching Obsoletes list for channel: rhel-i386-es-3-extras...

Fetching Obsoletes list for channel: rhel-i386-es-3-devsuite...

Fetching rpm headers...
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The following packages you requested were not found:
lsof-4.63-4.1