Freebsd 6.2-current install on dell optiplex GX520

I am trying to install on dell GX520 platform. The boot starts ok and
sysinstall starts to run, with disk partitioning completed, it gives an
error message "unable to transfer the base distribution from acd0".   I have
burned 4 cd's of the boot disk so far and I can reproduce this issue
consistently. 

 

What is wrong here. Is there some other thing clashing with the cdrom driver
routine, please give me your insight as to what problem this is. 

 

Thanks

Guru