I recently bought this lot of stuff on ebay. I got it today and left it in the box for about 5 hours because it is cold out and the box was on a truck and didn't want to chance condensation. Anyhow, I get it out and am pleased with the condition of the items but... I put the lenses on my Rebel Xt and the 70-300 gives me an error 99 and the 28-80 won't AF. I tried MF and it will take the picture but then it gives me an error 99. Will these lenses not work on my camera? I got the lot of stuff because I needed a film body for school and thought the lenses would be a nice bonus as I could use them with my XT, was I wrong? Thanks.