Hi,
I'm using Hibernate with XDoclet,
And i wonder if in general it's a good idea or not to put xdoclet generated files (like *.hbm.xml) under source control or if only java file are sufficent?

I always have my generated files, whether *.xml or *.hbm.xml or whaterver -- output to a directory (such as ${basedir}/target) that is not checked in/out of the repository. As a policy anyway

Every time you regenerate your mapping files based on changes made to one Java class all of your hbm.xml files are "touched", particularly if you tell your schema-export to use force.
It's a lot easier to just checkin the changed Java source, less opportunity for confusion. If other people are sharing the repository the timestamps on the generated files may cause their sandbox version to miss regenerating a file that it should have.