Converting GMT time to user's local time

All -
I need your help in converting GMT time to a local time of any
particular user using XSL.
I receive input XML like from the TV channel provider:
<channel name="HBO">
<movie>
            <name>Braveheart</name>
            <date>24JAN2006</date>
            <showtime>21:00</showtime>
</movie>
</channel>
The <showtime> element has GMT time. I want to convert this time to a
user-specific time and return it to user in text format. Example: If a
user logs in from Singapore, he should see this time as his own local
time and so on.
Thanks.
- Lalit




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