CLONE -directory checksum error when expanding confluence download tar file

downloaded [ http://www.atlassian.com/software/Download.jspa?file=http://www.atlassian.com/software/confluence/downloads/binary/confluence-2.5.8.tar.gz ] to aix 5.3. unzipped via gunzip, then attempted to expand resulting tar to install directory:
tar -xvf /tmp/confluence-2.5.8.tar
got message:
tar: directory checksum error (804401144 != 39419)

the archive is only partially extracted.

the 2.6.2 WAR tar seems to extact OK.