At any time, only the latest is available, currently RH EL 5.6 .
A package list : Only when you have a paid Redhat account.
The latest EL5.6 source code = SRC.RPMS, is open source, and is accessible :
http://ftp.redhat.com/pub/redhat/lin...r/en/os/SRPMS/
( Older build versions are included too.)
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