In reply to david100:
Thanks Tony, I'll call them today.
David, yes you can get replacement ones.
If you are using the old style, there are Youtube videos and pdf's
www.jetboil.com/WorkArea/DownloadAsset.aspx?id=817
The parts are pretty cheap
http://www.facewest.co.uk/Jetboil-Maintenance.html?gclid=CjwKEAjwl7ieBRCK2r...
If it's the new style, I think you can get them, a bit of googling will find it.
If you are a geek you could try and DIY it.
It is basically the igniter from a cigarette lighter. We used to take them apart as kids to zap each other