Hi Chris
Add this into you xen.ini file
TimeZone="Greenwich Mean Time" \
ManualOverride=yes \
Daylight=yes \
Start=030507 \
End=100507 \
TimeZoneName="GMT Standard Time" \
DayLightName="GMT Daylight Time"
It doesnt show clearly but there is a space on a new line that follows a \
that should do the trick....