duplicting a CD

[Stephen Adler]

Guys,

I just ran across an interesting problem I never really thought about. I 
need to duplicate a bootable dvd. Do I do this using the following 
command...

dd if=/dev/sdd of=/tmpspace/dvdiwanttodup.iso

then burn the .iso to the new dvd?

I have a feeling mounting the DVD, then taring up its contents isn't 
going to really work.

Thanks in advance.

Cheers. Steve.