Nissan Patrol 2000: Lost fifth gear

While on an interstate trip recently in my 2000 Nissan Patrol I was driving in fifth gear when all of a sudden bang went the gearbox and I did not have any traction in this gear. I did have the other gears but the gearbox is making a growling sound when in neutral or first gear. My mechanic said that Nissan did have problems with fifth gear breaking and he thought that Nissan had recalled the cars to have this problem rectified or that at least Nissan would repair as and when it happened. I purchased this car from brand new and have never received any letters saying there was any problem with the gearbox. Given that I have only clocked up about 99,000 km I checked with a Nissan dealer who referred it to Nissan and the answer I received was that due to the age of the car they would not warrant any repairs. Has this happened to many others and should not Nissan honour their recall given that they were aware of the problem?