java - Problems with ElementCollection / MappedSuperclass / AssociationOverride -

i have troubles override association. reading javadoc http://download.oracle.com/javaee/6/api/javax/persistence/collectiontable.html can read "see also: elementcollection, attributeoverride, associationoverride, column" wich gives assume can use it.. don't know how doesn't works

@mappedsuperclass public class abstractuser {  [...] public string getlastname() { ...}     @elementcollection     @collectiontable(joincolumns=@joincolumn(name="user_id"))     @column(name="nickname")     public set<string> getnicknames() { ... }  

implements

@entity @table(name="users") @table(name="user_rfcs") @associationoverride(name = "nicknames",         jointable = @jointable(name = "user_nicknames", joincolumns = @joincolumn(name = "user_id")) ) public class user extends abstractuser { [...] }    @entity @table(name="user_rfcs") @associationoverride(name = "nicknames",         jointable = @jointable(name = "user_rfc_nicknames", joincolumns = @joincolumn(name = "user_id")) ) public class userrfc extends abstractuser  {        [...] } 

@associationoverride mentioned in "see also" section due following:

if embeddable class contains references other entities, default values columns corresponding references may overridden means of associationoverride and/or associationoverrides annotations.

from other side, @associationoverride's javadoc says can applied entity relationships, not collections of primitives:

used override mapping entity relationship

so, looks can't @associationoverride, , have override getnicknames() method different annotations in subclasses.