we are attempting to fit hibernate to an existing database schema, so we are using composite-map-keys. however, we have a table where one or more of the key-property's in the composite-map-key may be null. however (i can't find any documentation to support this), it seems that hibernate cannot handle null values since the sql it generates is just wrong (not-null="false" doesn't change anything). two questions: is this indeed the case (null values not supported for key-property's in a composite-map-key)? and if so, why (the sql to generate support it is not that difficult)?