NetworkManager Problem

[Eric Tanguy <eric tanguy univ-nantes fr>]

I would like to continue to use NetworkManager and not going back to the 
old fashion but i can't figure out how to make it use a static IP 
address. If i right click on the networkmanager icon i can select 
connection modification but in the Auto eth0 all is greyed and can't be 
modified. How can i do this ?
Thanks
Eric