Solaris is always a bit different from Linx even in such minor issues. Timezone files are located in /usr/share/lib/zoneinfo. If your timezone is missing then just generate all of them by running:
# /usr/sbin/zic africa asia australasia europe northamerica southamerica
Then change TZ parameter in /etc/TIMEZONE to your timezone like:
TZ=Asia/Novosibirsk
Reboot for changes to take effect.
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