For the first 6-8 months of having the card (now 2 or so years ago) they were extremely trigger happy. Happened a lot when I would travel Intl overseas, and then make a purchase on the Internet from a US retailer (like Amazon.com) and then charge a hotel or airfare with another US retailer. After about 1/2 a dozen trigger pullings, they finally stopped. The last time I've had this happen was back in October, when I was up in Canada (Toronto) for 2 nights. It ended up being bout a dozen GTE Airphone calls that apparently triggered it - the system is designed to recongnize a lot of like transactions in a row.

Like others have said - VERY inconvienent - but probably overall worthwhile. I have other cards, so it's usually not too big of a deal, and a simple phone call (I have an intl cell so it's only two button presses away, but I can imagine for others out of the coutnry it could be messy.