Hello Experts,
While installing process engine on linux RHEL 6.1 it trows error.

According to PE 6.7sp1 release notes, I have to run the dm_set_server_env.sh script to avoid this error.But I had run this befor installation again no luck.Please help me if you know what the problem is.
PE 6.7 sp1 Release notes
=================================================
Defect # BPM-5357
Description of known problems
Process Engine installer reports warnings about DAR installation failures.
On non-Windows platforms, ensure that you set the Documentum
environment variables before running the installer. If you do not set these
variables, then the installer will report warnings about DAR files that are
not installed.
As a workaround, before installing Process Engine 6.5 on a non-Windows
platform, ensure that you source the script dm_set_server_env.csh or
script dm_set_server_env.sh (depending on the shell in which you run),
in the Content Server installation owner’s environment. This sets the
environment variables required by the installer. The script is located in
$DM_HOME/bin. To source the script in the C shell, for example, type:
source ./dm_set_server_env.csh. Alternatively, you can manually set up all
the environment variables as listed in the Content Server Installation Guide.
Thanks in advance