Errors during 6.5.1 install on Solaris

Download the tar, ran tar xvf c55e1na.tar

ran ./install & after several tab keys I get

Installing Domino Server kits …

Fatal Error extracting filegroup.

cd /opt/lotus/notes/65010/sunspa; /usr/bin/cat /home/admest/sol/sets/fgroups/fg20.

taz | uncompress -c | /usr/bin/tar xvf -

tar: directory checksum error

I have downloaded again a new file and still errors - has anyone managed to install the update on solaris 8/Sparc over 6.5 yet - any ideas on how to get around it?