A user reported
that his frontpage had been replaced with Islamistic propaganda and that his deactivated and forgotten Postguestbook sent some 25.000 mails with similar content.
has not been updated since 2002 and there is currently no maintainer for the project. The pnTeam suggests to uninstall Postguestbook and to remove it from the webspace. It's not sufficient to only deactive the module. It must be removed from the webspace
is an up-to-date guestbook module which can completely be customized via pnRender templates. And Philipp Niethammer is its active maintainer.