LOWER operand with nested LOCALNAME operand not work with SQL2

Below query was running successful using Query.SQL languange:
SELECT * FROM nt:file WHERE (CONTAINS(*, 'Jon') OR LOWER(fn:name()) LIKE '%jon%') AND jcr:path LIKE '/Resources/%' ORDER BY jcr:score()

But equivalent next query in Query.JCR_SQL2 will fail with exception UnsupportedRepositoryOperationException():
SELECT * FROM [nt:file] WHERE (CONTAINS([nt:file].*, 'Jon') OR LOWER(LOCALNAME()) LIKE '%jon%') AND ISDESCENDANTNODE('/Resources') ORDER BY SCORE()

From my investigation seems LOWER function will not work with nested function LOCALNAME. According to section "6.7.32 LowerCase" JCR 2.0 Specs, LOWER operand able to work on DynamicOperand argument.