British Summer Time date/time display

Can you guys can help or point me at some place that would help me decide how to display a table of date/time related data. The data is from events that happen every day at approximately midnight GMT. So I need times to be displayed as 00:00:00-ish prior to March 29th 2004, and as 01:00:00 ish after this date and for the next 6 months.

What is a the typical way to ensure this? Do you have to store the list of dates of when the daylight saving starts and ends and query this every time? or is there some neater way of doing it?

Thanks
Kester