how to import a 11GR2 database in a 11gr1 or 10GR2 database

Let's suppose you have a 11.2.0.X Oracle database and you want to import it ( entire or only some schemas )  into a 11.1.0.7 database or 10.2.0.X database

Solution : export from the beginning , with a compatible parameter :
expdp version=10.2
or
expdp version=11.1

After that, take the dump, move it to an oracle datapump directory on the destination server and start the import