Yum hangs in Redhat Linux

[john2009]

I am trying to install a yum package using YUM utility. It hangs after transaction checking...
yum.log is clear and linux system log did not contain any message. can someone help me ?

$sudo yum install whp-apache
Loading "rhnplugin" plugin
Loading "security" plugin
This system is not registered with RHN.
RHN support will be disabled.
Setting up Install Process
Parsing package install arguments
Resolving Dependencies
--> Running transaction check
---> Package whp-apache-2.2.noarch 0:6.0.0.0-1 set to be updated
--> Processing Dependency: apache-ant-whp for package: whp-apache-2.2
--> Running transaction check
---> Package apache-ant-whp.noarch 0:1.0.0.0-1 set to be updated
--> Finished Dependency Resolution

Dependencies Resolved

================================================== ===========================
Package Arch Version Repository Size
================================================== ===========================
Installing:
whp-apache-2.2 noarch 6.0.0.0-1 spc-release 11 M
Installing for dependencies:
apache-ant-whp noarch 1.0.0.0-1 spc-release 9.3 M

Transaction Summary
================================================== ===========================
Install 2 Package(s)
Update 0 Package(s)
Remove 0 Package(s)

Total download size: 20 M
Is this ok [y/N]: Y
Downloading Packages:
(1/2): apache-ant-whp-1.0 100% |=========================| 9.3 MB 00:02
(2/2): whp-apache-2.2-6.0 100% |=========================| 11 MB 00:03
Running rpm_check_debug
Running Transaction Test
Finished Transaction Test
Transaction Test Succeeded
Running Transaction
Installing: apache-ant-whp ########## [1/2] -------------------> hang

[devils casper]

Have you tried to clean cache and rebuild database?

yum clean all
rm -f /var/lib/rpm/__db*   
db_verify /var/lib/rpm/Packages
rpm --rebuilddb