Time Zone GMT 5:30 not available in ViciDialNow CE 1.3

I'm from India and our time zone is GMT +5:30. But I could not see the same is ViciDial server configuration web interface, Only +5:00,+5:45 etc available. I've set GMT +5:30 in CentOS using system-config-date command to GMT +5:30 (Asia\Kalkatta).