User credentials in non-latin characters (SMP)

I am using SAP Mobile Platform to logon to SAP with user credentials that use non-latin characters such as: ๆพะฟหกด. (thai)

I can logon to SAP directly (SAPlogon) and through normal http web-services with these credentials, but when I try to logon through SMP and Kapsel plug-in, it fails.

This is the test I do:

I try to login with the test user test_ๆพะฟหกด

I go to SAP Mobile Platform Administration and Monitoring and find the failed request with the user: test_???????

Another test I also tried:

I try to login with a non-existing user test_äú

In the logs I find the request made from the following user: test_??

Do I need to change the language of SMP to support other characters? Do I need to change its encoding to utf-8?

If so, how can I do this?

Thanks in advance!