Setting timezone of org-mode

I'm just getting started with org-mode, and reall开发者_StackOverflowy like it so far. I work in London with xemacs running on OpenVMS based on the East Coast US. Is there any way to get org-mode to use a timezone other than the server's default?

I've tried:

(setq calendar-time-zone 0)
(setq calendar-standard-time-zone-name "GMT")
(setq calendar-daylight-time-zone-name "GDT")

with no luck.

Turns out:

(set-time-zone-rule "GMT-1")

works.

I'm not entirely clear why this:

(set-time-zone-rule "BST")

gives the wrong output (it results in times 1 hour early, even though BST is the current timezone string for London, UK).

(set-time-zone-rule "<TZ*>")

where

<TZ*>