appplication using DOM Level 1 / Level 2

Hello,

A little question about compatibility between DOM leve 1 and 2:

Should I rely on the fact that an application (in my case a Java one)
using the interfaces of the DOM Level 1 binding should also run on an
implementation of the DOM Level 2 without rebuilding it? In other words,
is the intend of DOM Level 2 interfaces to be compatible with DOM Level
1 ones without any modifications in the deployment process?

Thanks,
-- 
Christophe