:Linux.com: How You Can Digitally Sign OpenOffice.org Documents
Linux.com: How You Can Digitally Sign OpenOffice.org Documents Oct 12, 2006, 10 :30 UTC (5 Talkback[s]) (7224 reads) (Other stories by Dmitri Popov)
"The ability to digitally sign OpenOffice.org documents is a boon for users who want to make their document exchange and collaboration secure. Using digital signatures in OpenOffice.org is not that difficult, but configuring it involves several steps that are far from obvious.
"Before you enable the digital signatures feature in OpenOffice.org, you must obtain a digital certificate and install it on your machine..."