[Zope] Formulator error

Hello All, I have a shared Zope account at Zettai.net. I need to use formulator for a project. Something strange is happening: when I add a "Formulator Form" and click in the "Settings" TAB, I get this error: Error Type: AttributeError Error Value: header The formulator version is the last: 1.5.0 Anybody has an idea ?? Thanks Parra