Steps to install mailman on plesk server

1] Download it from the below link :-
root@server]# wget http://download1.parallels.com/Plesk/Plesk8.3/CentOS5/swsoft_installer_v3.3.0_build080201.09_os_CentOS_5_i386
2] after downloading the above tar file make it permission to 755
3] execute it and the scripts automatically starts and follow the steps.