Newbie Question

when I try to create an object Page Template in Zope with Internet Explorer 5, Zope generate an error :
Error Type: Undefined
Error Value: You are not allowed to access manage_page_header in this context not found in 'here/manage_page_header', at line 1, column 1
I can't locate the problem but I suppose it involves the cookies (however cookies are enables)

I'm sure it is a browser problem because with Netscape there is no problem when I create a Page Template.

If somebody have an idea....

Thanks in advance. William