HSQL (Hypersonic SQL) throwing error when using NLSSORT

I am getting the following error when running unit tests using HSQL.

Cause: java.sql.SQLSyntaxErrorException: user lacks privilege or object not found: NLSSORT ; bad SQL grammar []; nested exception is java.sql.SQLSyntaxErrorException: user lacks privilege or object not found: NLSSORT

I have selected to use to oracle dialect in the HSQL configurations which work well for other Oracle specific queries.

Here is the query that is failing;

 select COUNTRY_CODE, COUNTRY_E_DESC

                from COUNTRY

                order by nlssort(COUNTRY_E_DESC ,'NLS_SORT=BINARY_AI')

Is there another configuration I need to set to get HSQL to use NLSSORT?