ALTER USER does not accept TO_TIMESTAMP in validity

Hi everyone,

i am running into an issue where i cannot find the solution and where the SAP support just tells me to order an expert on demand:

Execute:

ALTER USER TESTUSER VALID UNTIL TO_TIMESTAMP ('20160129', 'YYYYMMDD');

This one is an easy one as the validity would also be accepted without the conversion through "TO_TIMESTAMP" but this is the simplest example. This Query leads to:

Could not execute 'ALTER USER TESTUSER VALID UNTIL TO_TIMESTAMP ('20160129', 'YYYYMMDD')'
SAP DBTech JDBC: [257]: sql syntax error: incorrect syntax near "TO_TIMESTAMP": line 1 col 31 (at pos 31)

But should be accepted as this is a correct timestamp:

SELECT TO_TIMESTAMP ('20160129', 'YYYYMMDD') "to timestamp" FROM DUMMY;
29.01.2016 00:00:00.0

I'd assume that this should be working - but where is the error?

Thanks in advance for your help!