Question

Just been searching the internet for my next lens. As I want a 70-300mm lens. I came across a Sigma one on Amazon;

Sigma 70-300mm f/4-5.6 DL-M “Motorized” DG Macro Telephoto Zoom Lens with Built-in Motor Drive for Nikon SLR Cameras Including D40, D40X, & D60

http://www.amazon.co.uk/Sigma-70-300mm-Motorized-Telephoto-Including/dp/B0016N17ES/ref=sr_1_2?ie=UTF8&qid=1242557897&sr=8-2

According to the page, the work “Motorized” means that it will give me auto-focus on the Nikon D40. Is this all correct? I know that sigma have like HSM for that sort of stuff but it didn’t mention it on the page.

Thanks for anyone who will help.