See Bug 144029 for details. This bug is the equivalent issue for RHEL2.1-ia64.
The same regression was introduced with the E7 security errata...
It's slated for the next RHEL21 security errata; I'll update when it's actually
A fix for this problem has also been committed to the RHEL2.1 U7
patch pool (in kernel version 2.4.18-e.53)
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.