[Zope] 2.6.3/product/security/PageTemplateFile problem

hi! i have a "small" problem with PageTemplateFiles i use in products. the problem is, that none of my products which worked fine under zope <= 2.6.2 are working under 2.6.3/2.7.0-rc1. i always get "You are not allowed to access '' in this context" when i try to access a PageTemplateFile, even if i declare them public. normal methods are still working correct. these are the lines, where the problem(s) must be: ... __roles__ = ( ) security = ClassSecurityInfo( ) security.setDefaultAccess( 'deny' ) ... security.declarePublic( 'index_html' ) index_html = PageTemplateFile( 'ZPT/index_html.zpt', globals( ) ) ... any idea what i'm doing wrong? thanx in advance - sifu