[Tagging] Opening hours + daylight saving time

[Warin]

Hi,

I need to combine daylight saving times with opening hours ...
For example
open 8:300 to 17:00, except for daylight saving times where it is open 
8:30 to 18:00.


Possible ?
opening_hours=ndst 8:30-17:00; dst 8:30-18:00

where
ndst = non daylight saving time
dst = daylight saving time

dst is suggested in 
http://wiki.openstreetmap.org/wiki/Proposed_features/access_restrictions_1.5