I just got my first DSLR for Christmas and have a few question. I got D40x kit with the 18-55 kit lense and so far I love it. I am looking for another lense with a little more magnification. I want to maintain all the features of the camera and from what I understand this limits me to Nikkor AF-S or AF-I lenses. Does anyone beside Nikon make lenses that would fit my D40x and also maintain all the auto features? Also, what type of teleconverter can be used? Thanks.