Alarm with horn?

Hello,I just wanted to ask something. Someone set my car alarm off somehow and the only reason I noticed was because the post man told me the lights were flashing and the alarm was beeping. I went out to the car and it the alarm sound is very quiet, you canonly just hear it from my house even though I can see my car from my living room window.
Anyway what I was wanting to know is is there any way of activating the horn with the alarm like some cars have? Ive had a look through VCDS and can only see something about activating the beep with the alarm when acivated, deactivated?

Thanks

Chris

Yeah Ive got a better chnce of hearing the microwave go off 2 houses down than I do of hearing my car alarm parked infront of my house...