[SunHELP] Help quick! Daylight saving How does it work?

Hello All

I hope you gurus can help.

Its rather complicated but we have a client whose box we 
sort of "look after". ie i can only get access to it via 
someone on the phone..  anyway..

I need to find how we can confirm the daylight saving 
settings on it and if it will switch over this weekend. 

We cannot test it by changing the date and waiting for 
it to switch over and then switch the date back to the 
current time because its in production.

I always thought that daylight saving was "automatic" 
depending on the timezone settings. Is that right?

The client is asking about installing /usr/sbin/rtc 
into a cron job to change the time?  We dont have that 
program installed on the system. Where do we get a copy 
of that program? What exactly does it do? We we need it 
at all given that the timezone has been set on the machine.

when we type the "date" command we get the current time and 
also the timezone as EST. doesnt that mean that we will have 
the daylight saving switching over as required?

How can I tell if the time zone settings are correct and 
that it will switch at the appropriate time. Is that a 
file on the system i can look at and confirm this?

Hope there is enough info for yous all to help !!

Regards 
TW Foong