Why Does Ubuntu "Flip" My CD Drives?

[bill g]

I'm running Ubuntu on a machine with two CD drives. Prior to Ubuntu,
using a 2.4 kernel,  the drive identified as /dev/hdc was the drive I
used to burn and play CD's.   Now, on Ubuntu, the same drive is still
/dev/hdc, but only /dev/hdd will permit burning and playing CD's. 
I've noticed the same behavior using a 2.6 kernel in other
distributions.

Do 2.6 kernels, in fact, treat CD drives differently that 2.4 kernels?
 Is there a way to return to the previous behavior?

billg