transaction.RollbackException + EJB

Hi,
I am trying to write into two tables via one method in the Session bean which References the corr. Entity Beans. However I get the transaction.RollbackExceptio.

Here is what I am doing

In the Session bean in one method I have

try{
int year = semester4.getYear();
String semester = semester4.getSemester();
System.out.println("Came inside .. just before isCourseAddedAdminMode");

LocalPre_course pre_course = pre_courseHome.create(course_number, prerequisite);
LocalCourse course = courseHome.create(call_number, course_number, semester, year, course_name,
department, credit, prerequisite, desc, total_seats, avail_seats, f_ssn);
}

catch(Exception ex){
//throw new EJBException(ex.getMessage());
return false;
}
return true;
}

in the corr. entity beans
//This is the pre_course bean

public String ejbCreate(String course_number, String p_course)
throws CreateException{

System.out.println("Came inside Pre_CourseEntityBean.. just before isAdded");

setCourse_number(course_number);
setP_course(p_course);

return null;
}

//this is the courseBean

public String ejbCreate(String call_number, String course_number,String semester, int year,
String course_name, String department,int credit, String prerequisite,
String desc, int total_seats,int avail_seats, int f_ssn)
throws CreateException{ //should throw more exceptions !!!!!!!

System.out.println("Came inside CourseEntityBean.. just before isAdded");
setCall_number(call_number);
setCourse_number(course_number);
setSemester(semester);
setYear(year);
setCourse_name(course_name);
setDepartment(department);
setCredit(credit);
setPrerequisite(prerequisite);
setDesc(desc);
setTotal_seats(total_seats);
setAvail_seats(avail_seats);
setF_ssn(f_ssn);

return null;
}

//screendump on server window

Came inside .. just before isCourseAdded
Came inside .. just before isCourseAdded (ADMINCONTROLLER!)
Came inside .. just before isCourseAddedAdminMode
Came inside Pre_CourseEntityBean.. just before isAdded
Came inside CourseEntityBean.. just before isAdded
java.rmi.ServerException: RemoteException occurred in server thread; nested exce
ption is:
java.rmi.RemoteException: Transaction aborted (possibly due to transacti
on time out).; nested exception is: javax.transaction.RollbackException: Transac
tion marked for rollback; nested exception is:
javax.transaction.RollbackException: Transaction marked for rollback
java.rmi.RemoteException: Transaction aborted (possibly due to transaction time
out).; nested exception is: javax.transaction.RollbackException: Transaction mar
ked for rollback; nested exception is:
javax.transaction.RollbackException: Transaction marked for rollback
javax.transaction.RollbackException: Transaction marked for rollback
<<no stack trace available>>

I cannot figure out the problem ,,,, since the println statements works its just before or when the set methods it called in the Entity I believe

I remain waiting eagerly for an answer