how to access LVM's from another system?

[Default User]

Hi! 

I am getting ready to reinstall Ubuntu 7.04 and I am thinking that if I
let it do the default LVM setup, I may need to access the LVM
partition(s) from outside, for example to rescue the data from a broken
LVM setup, or just to transfer data to/from the LVM setup. 

In the past I was horrified to find that I could not access Ubuntu files
in an LVM setup from a Debian setup with normal, non-LVM partitions. Is
there a way to do so?  If not, I may be better off in the long run just
installing Ubuntu with normal, non-LVM partitions.  

Any thoughts?