Power Train Driveline problems of the 2003 BMW X5

2003 BMW X5 4. 4i transfer case/front drive shaft failed leaving car stranded on a railroad crossing with no power. Rr lights began to flash but manged to push car off tracks in time once we found help (too heavy to push alone). Same failure at 90k miles had stranded car on a local street about 2. 5 years earlier. BMW replaced transfer case and front drive shaft under certified pre-owned warrantee. Current failure occurred on transfer case/drive shaft less than 40k miles / 2. 5 years old. Same failure is well documented with numerous other owners on various internet message boards. Research suggests the failure is due to a design flaw invoving insufficient spline engagement and poor placement of a/c condesate drain directly above tranfer case / shaft connection causing accelerated rusting of drive shaft splines which eventually weaken and strip out. Attempted to get BMW to cover repair out-of-warrantee due to circumstances of early failure fo a drivetrain part. Multiple calls (messages for service managers) to two local dealerships went unreturned. Call to Bmwna was unhelpful - would not take any action until car was towed to a dealership for inspection at my expense and would (at best) be repaired with same parts of poor design.