I am not quite familiar with xscron, but as it is based on javascript you should compare it to UTC time. Javasript returns the timstamp in UTC format (eg. 1 January 1970 00:00:00 UTC)
If the usage of UTC timestamp does not solve your issue maybe somebody else has some deeper knowledge.
SELECT CURRENT_UTCTIMESTAMP "Coordinated Universal Timestamp" FROM DUMMY;
Hope it helps,
Andreas