Hi!
We're using your product version 3.4.0.3201 in Moscow, Russia. Domain setting "Timezone" is "Moscow, Russia". All is working perfect, service flags work correct, using different time offset. I think, it's hardcoded.
This year in our country for Moscow was rejected timezone change from winter to summer time (were GMT+3 and GMT+4, now only GMT+4). Does pbxnsip consider this fact? I post this question, because I saw that pbxnsip doesn't use system timezone setting, using it's own from Domain or General Settings.
Best regards.