Can it take so long?

I had a parcel especially air freighted on the 15th January 2015 by USPS First Class International (tracking # LJ***US) and I was told it would take 3 to 4 weeks to get to Cape Town from Arizona. Now 9 weeks later still no sign of the parcel and absolutely no-one can assist me. The best I get is that they think it may be in Johannesburg but not quite sure?