Tire Bulge problems of the 2005 Volvo S60

We have a 2005 Volvo S60r. After hitting a pothole and destroying the right front tire and rim we replaced all four tires and wheels with o. E. M. 17" wheels and pirelli p6 tires. Less than 1000 miles later two of the tires developed bulges in the sidewall at the exact same location on each tire. Kline Volvo would do nothing about it saying it was road hazard damage, but these tires didn't hit anything that doesn't occur in the normal course of driving, small road irregularities at low speed, etc. Pirelli and Volvo corporate were of no help either, both just referring me back to the dealer where I bought the tire. There are many, many pages of complaints on various internet sites about this tire developing sidewall bulges and having blowouts. Somebody should make pirelli recall these tires before someone is killed.