Oh man, this new forum is confusing. I hope this is the right place to ask.
I wonder if anybody has a good idea about how I can copy a multi valued attribute from one object, to another multi valued attribute on onother object.
My experience is, that just setting the src attr on the second object to the src attr from the first object, just gives the first value in the multi valued attribute.
Otherwhise you need to loop over it with a for each and add all values one by one.
Since the value type can only be specified as dn, string, integer etc, there is not an option to specify that the source attribute value should be a node set (when setting it).
So looping must be it,
First clearing the attribute, and then adding values one by one.