Passing nvarchar param values to scalar UDF from XSJS

Hi,

I've created a few scalar UDFs (User Defined Functions) in HANA repository via an XS project. They work really nice from SAP HANA Studio SQL Console, but despite many attempts I've not managed to pass nvarchar param values from XSJS. Let me show the problem on an example:

This very simplistic scalar UDF is executed without any problems and returns a result at once in SQL Console, however within XSJS I get an error:

I have tried with different users and privileges, different functions (scalar UDFs with integer parameters are working fine), .xssqlcc, but without success.

Thank you in advance for your help!

Regards

Michal