NAT: Comparison with UNICODE Superdescriptor

Compare of a UNICODE Superdescriptor (of an Adabas file) against a key that is composed identically does not work correctly when the comparison is executed by Natural. This affects the following statement:
READ ... ENDING AT
HISTOGRAM ... ENDING AT
IF ...

Examples:
READ ... BY UNICODE-SP ... ENDING AT #unicode-key
IF UNICODE-SP > #unicode-key

Note: Comparisons executed by Adabas work correctly, as in
READ / HISTOGRAM ... STARTING FROM
READ / HISTOGRAM ... TO
FIND

Natural should also be able to execute these comparisons correctly.