[Zope] dtml errors and page refresh

I am using zope 2.15 and apache 1.3.9 on debian box serving zope from an apache rewrite and pcgi. When I sam a dtml document with errors, I get the normal zope error screen and then when I het the back button in the browser to edit my template, I get the "warning, page has expired" and I lose my changes. How can I oversome this? Thanks, adam