Problem with getdate()

I have a very simple function that relies on getdate() (a standard PHP function). However, I noticed a very bizarre behavior: when I invoke my function from outside a WordPress context the function returns dates in the local timezone. When I invoke the exact same function from within a WordPress context, the function returns dates in gmt!! How can this be? I don’t see any WordPress override of this function, so I’m very confused about why this is happening. Any help would be greatly appreciated.

Thank you.

David