Install / Configure Request Tracker 4.0.19 on CentOS / RHEL

Dear all,
What is Request Tracker ?

Request Tracker, commonly abbreviated to RT, is a ticket-tracking system written in Perl used to coordinate tasks and manage requests among a community of users. Rt’s first release in 1996 was written by Jesse Vincent, who later formed Best Practical Solutions LLC to distribute, develop, and support the package. RT is open source (FOSS) and distributed under the GNU General Public License.