Front Seat Power Adjust problems of the 2004 Infiniti G35

Failure of drivers side seat frame due to cracking twice. Once at 26,177 miles on 8/8/06 and again at 60,815 miles on 5/20/10. The way I became aware of the failure is that both times it interfered with the power seat operation. I have been the only driver of this vehicle since it was new. I am not a big person, male, 5'8" 160lbs. The vehicle is perfectly maintained, looks new and all service records are available. Replaced under warranty the first time the seat frame cracked and replaced the second time out of warranty at the same infinity dealership. Inquired from the dealer if this was a safety issue and they would not answer. Contacted the manufacturer directly twice to get additional info and inquire if this was a safety issue. They said the first time that they would not tell me one way or the other. If they felt it was a safety issue they would self report it directly to the proper party. They did not respond to my second inquiry. This did not seem appropriate to me after the issues with Toyota. I have saved the part from the more recent replacement in case further inspection was necessary.