Realport 1.9-35 installation on RHEL 5.11

I am trying to install the RealPort driver version 1.9-35 on RHEL 5.11 but I am getting the following error message when I run rpmbuild --rebuild 40002086_W.src.rpm

Installing 40002086_W.src.rpm
error: unpacking of archive failed on file /usr/src/redhat/SPECS/dgrp-1.9.spec;56d9226d: cpio: MD5 sum mismatch
error: 40002086_W.src.rpm cannot be installed

It looks to me like there is a problem with the .spec file.

My kernel version is 2.6.18-408.el5


The following knowledge base article should address this: