I wouldn't worry about it, mine is like this also. Btw, have you discovered that you can have the windows come down automatically if you turn the key to one side when opening it, and vice versa, closing all windows that are opening when locking it? 
Turn the key to one side? Whilst in the lock i take it (assuming the wii type sensor thing wasn't invented in car keys back then

).
Might have a look and see if i can find a leak in the pipes. I'm happy to live with it tho, now that i know it's a standard thing.

If i have to unlock the car with the key, wont the alarm go off when i open the door?? That used to happen in my Vectra and it was effin' annoying!!