Hello, Sorry for the cross-posting but I've posted before on the zope list without reply. The following looks like to be a bug on the lookup of the request attributes. If request doesn't have the attribute HTTP_X_FORWARDED_FOR, the following TALES expression should return REMOTE_ADDR. In fact, it returns the empty string. <p tal:content="request/HTTP_X_FORWARDED_FOR | request/REMOTE_ADDR"></p> Naturally, the following works ok: <p tal:content="python: request['HTTP_X_FORWARDED_FOR'] or request['REMOTE_ADDR']"></p> Shall I file it as a bug or am I missing something? Cheers, Fernando