did you call your paid for tech support ?
or is this the " free" unsupported and NOT updated RHEL5 . to get updates on that one you need to regester with red hat and pay them . or install the centOS5.3 ( may not work on RHEL5 - not upgraded to 5.3 - ) repo files
http://wiki.centos.org/AdditionalResources/Repositories
but installing and using CentOS as your OS would be a better option if you are using the "free" rhel5
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it also looks like you want , and are trying to, install a rhel 4 package on rhel 5 .
