According GSM specification 03.40 SMS include time stamp which format is the local time and the time zone parameter. The time zone parameter indicates the difference, expressed in quarters of an hour, between local time and GMT time.
We have used this complete time stamp for embedded units time setting over time zones, but it does not work with most of operator particular them who use Nokias SMSC.
According three operators comments seems that Nokia do not support that time zone parameter. Is there any possibility to use it?