Porsche Cars North America Sold cars with defective motors, prone to blow out Internet

I bought a 2002 911 C4 Porsche used from my best friend in late 2007.  My friend had only driven the car 27,000 miles.  I bought the car from him knowing that he had the car serviced by the dealer, and was never in any accidents.  After I bought the car, I had it serviced regularly by a local Porsche mechanic.

The car started to lose radiator fluid, and not being a car expert, i simply added more radiator fluid.  Once i hit 44,000 miles on the car, the engine seized up.  seems that due to an engine/cylinder design flaw, the radiator fluid was leaking into the engine and mixing with the oil, and as you can guess, my engine seized up.

I now need a new $20,000 engine after only 44,000 miles?  I did call Porsche and logged a complaint.  They said there was nothing they could do, since i was out of warranty, did not buy the car from Porsche and did not have the car serviced by Porsche.  However, when you look on the web, seems there is a common defect on these engines as it looks pretty common that the Porsche engines blow out from any point after 20,000 miles.  Hard to believe that you buy a $100k car and the engine has a shorter life span than an American car?

Any Porsche expert you speak to claims that everyone including Porsche is aware of the problem, but everyone is afraid to take on Porsche.

Is there anyone that can help?