In RHEL 5, yum update gives error message "failed to retrieve getPackage/packagename error was [Errno 7] HTTP Exception (BadStatusLine)"

Issue

yum update gives following error message

Transaction Summary
================================================================================
Install       1 Package(s)
Upgrade      25 Package(s)
Total download size: 40 M
Downloading Packages:
Error Downloading Packages:
  device-mapper-multipath-0.4.7-34.el5_5.1.x86_64: failed to retrieve getPackage/device-mapper-multipath-0.4.7-34.el5_5.1.x86_64.rpm from rhel-x86_64-server-5
error was [Errno 7] HTTP Exception (BadStatusLine):
  nspr-4.8.4-1.el5_4.i386: failed to retrieve getPackage/nspr-4.8.4-1.el5_4.i386.rpm from rhel-x86_64-server-5
error was [Errno 7] HTTP Exception (BadStatusLine):