Convert Tz posix time zone string to Utc-xx && vice versa

anybody knows how to convert a tz posix time zone string example "CET-1CEST,M3.5.0,M10.5.0/3" to an开发者_运维百科 utc string like "(UTC-12:00) International Date Line West" in javascript

and the other way around ?

thank you

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can you use a lookup?

http://code.google.com/p/x-wrt/source/browse/trunk/package/webif/files/usr/lib/webif/timezones.csv?r=2936

DEMO HERE