im having problems with my iPhone 3gs.

the button on the side which swaps between vibrate and loud randomly vibrates when its set to vibrate.
sometimes its a stint of about 10 - 15 vibrations one after another and sometimes just the odd one.
it can get quite annoying thinking that i might always have a text message etc...

now i am unsure on my warranty.
I got the phone free from orange on a contract, but i dont know if i would have standard warranty from Apple??
ive only had the phoen about 3 months and its not even been dropped, so could this be an issue that Apple would have to look into, or will i be left with a bill to get the problem sorted myself??

Have you asked Orange? I think the Apple store will take it and repair it, and if they can't, they give you a replacement handset, or something along them lines.

Id contact Orange customer services and see what they say, and if they confuse matters, take it to the Apple store. After 28 days, the warranty will probably be with Apple rather than Orange anyway, but Orange may have some quick repair/replacement service in place for the iPhone.

Hmmm sounds like a loose connection as they normally vibrate when switching from sound mode to vibrate.
Do what Matty said and contact your service provider as I'm sure you will have a standard 12 month warranty with curtosy phone supplied.

Check for any firmware updates first in case it's a software glitch.

Under the Sale of Goods Act, any warranty is with Orange. Though you might well get fast service from Apple...

When I had a problem with a Nokia a few years ago I phoned orange and some bloke came the next evening and did a straight swap.

As already mentioned give Orange a buzz and see what they say

Thanks guys. Just gave orange a ring and they said that i didnt have the latest update. So they said plug it into itunes and see if it carries on after that. If it does they have the problem logged so i can just ring back and carry om from where i left off.

just to make you aware, there is a new update to the iPhone software being launched today. This will take it upto v4.2 I had the vibrate issue with my old iPhone 3g, putting a case on helps as when it was in my pocket i was knocking the switch a bit that caused the vibration.