[Zope] Dynamic charts and thread safety in Zope

I would like to run a product like ZGDChart or even a package like ReportLab through Zope but am concerned about threading issues? Is there a preferred way to use non-threadsafe products like these in a pure Zope, i.e. no CGI, environment? Maybe there's a way to use an external method to fire up a new process, create the chart/PDF for the user, and then kill the process. TIA, Walter