'Adds a "mobile" attribute to the request which is True or False
depending on whether the request should be considered to come from a
small-screen device such as a phone or a PDA'

@staticmethod
def process_request(request):

    if ('HTTP_X_OPERAMINI_FEATURES' in request.META):
        request.mobile = True
        return None
    if ('HTTP_ACCEPT' in request.META):
        s = request.META['HTTP_ACCEPT'].lower()
        if ('application/vnd.wap.xhtml+xml' in s):
            request.mobile = True
            return None
    if ('HTTP_USER_AGENT' in request.META):
        s = request.META['HTTP_USER_AGENT'].lower()
        for ua in search_strings:
            if (ua in s):
                request.mobile = True
                return None
    request.mobile = False
    return None
