mapping composite id as foreign key in a one-to-many association

I found this problem in mapping a composite id as foreign key in a one-to-many association:

here is my class with composite id:

class IntCau implements Serializable {
	static mapping = {
		table 'int_cau'
		version false
               id composite: ['c1', 'c2', 'c3'], generator: "assigned"
        }
        int c1
	char c2
	int c3
        static HasMany = [attScheds: AttSched, attProgrs: AttProgr]
	static mappedBy = [attScheds: 'causale', attProgrs: 'causale']
}

this is in relation one-to-many with two other classes (which have pretty much the same code):

class AttProgr {
	static mapping = {
		table 'att_sched'
		version false
		columns {
			causale column: ['c1_int_cau', 'c2_int_cau', 'c3_int_cau']
                }
                IntCau causale
}

i get this error:

Invocation of init method failed; nested exception is org.codehaus.groovy.grails.exceptions.InvalidPropertyException: No property found for name [attProgrs] for class [class IntCau]

so i insert the following declaration in the IntCau class:

List<AttSched> attScheds
List<AttProgr> attProgrs

and now the error became:

Invocation of init method failed; nested exception is org.hibernate.MappingException: Foreign key (FKE0C5693A41F5AA0A:att_progr [c1_int_cau, c2_int_cau, c3_int_cau,int_cau_c1,int_cau_c2,int_cau_c3])) must have same number of columns as the referenced primary key (int_cau [c1,c2,c3])

What's wrong? If i do the same on a class with simple foreign key all works! It's a bug?
I found a similar issue marked as resolved but my my problem still remain in new release 1.1
(http://jira.codehaus.org/browse/GRAILS-3506)

I also try to define the class in this way:

class AttProgr {
	static mapping = {
		table 'att_sched'
		version false
		columns {
			causale column: ['c1_int_cau', 'c2_int_cau', 'c3_int_cau']
                        int_cau_c1 column: 'c1_int_cau'
			int_cau_c2 column: 'c2_int_cau'
			int_cau_c3 column: 'c3_int_cau'
                }
                IntCau causale
                int int_cau_c1
	        char int_cau_c2
	        int int_cau_c3
}

compiling is ok, but in the browser i found the same exception.

and now the problem is in columns mapping:

Invocation of init method failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsDomainException: Error evaluating ORM mappings block for domain [AttProgr]: No such property: causale for class: GroovyObjectSupport_groovyProxy