Hi all, am hoping someone might be able to give me some advice

I recently got hold of an old Nikkor lens (see topic!); I couldn't resist, seeing as it was offered to me at such a good price!
From my research, mainly KenRockwell.com, I am under the impression that these old Ai lenses should work fine on some of the newer dSLR's, such as the D300... after entering the lens data into the camera as per the manual, I had no problems adjusting the aperture etc. and manual focusing was extremely smooth and simple... however, I cannot get the focus confirmation light/beep in the viewfinder to operate with the lens... is there a way to do this? Using my own judgement, the lens seems to be producing some extremely sharp images, but it would make the process a whole lot quicker if i could get this to work!! Any ideas?!
Thanks
