CMR and remote interface

[yuri375]

Hello,
I can't understand how to use container managed relationship fields.
I know that remote interface cannot include CMR fields. Why does this restriction exist? What is problem with that? WebLogic 6.1 seems to support CMR in remote interface anyway(?)
I've seen an example when set and get methods for cmr field are defined for bean class but not for remote interface. There is assign method instead in remote interface and it's defined like this:
void assignStudent(Student student) {
setStudent(student);
}
But why setStudent method could not be included into remote interface? I am not talking about Collections here, just simple 1:1 relationship.
Can I define another remote interface method like this:
Student retrieveStudent () {
return getStudent();
}