Missing finished tasks and successful workflows

Question

We have a InfoPath Form Library with Visual Studio Workflows on an MOSS 2007. Now to some of the form we're missing tasks in the tasklist and there isn't a status in the column of the workflow.

But the workflow had been started ... we're noticing, that all the affected forms have in common that the workflow (and the tasks of course) was finished.

Has somebody an idea what happened? Is there maybe a process or a setting that "cleans up" finished tasks and workflows?

Answer 1

I guess this explains what happened: http://programmerramblings.blogspot.com/2007/11/wss30-workflow-history-deleted-after-60.html