Rear Suspension Springs problems of the 2008 BMW X3

I was informed by an independent BMW repair shop that the rear springs were broken. A subsequent visit to a BMW dealer confirmed this. I was also informed by both the independent shop and the dealer that this was a common problem with 3 series Bmws. BMW of north America told me that this was not an item that would be covered under their cpo warranty or any other warranty. I would think that broken springs would affect handling and therefore constitute a safety hazard. Both the dealer and independent shop strongly recommended that I have them replaced as soon as possible.