C++ :: Threads Never Execute In Arbitrary Order?

Code:

void Arrival_MainThread::Body () {
t1 = new boost::thread((Arrive_Fctor()), 2);
t2 = new boost::thread((Arrive_Fctor()), 10000);
t3 = new boost::thread((Arrive_Fctor()), 3000);

Code:
class Arrive_Fctor {
public:
void operator()(int mean) {
m_Arrivals = new Arrivals(mean);
m_Arrivals->Activate();
#ifndef NO_RESOURCE

[code].....

The order of arrivals always appear as 3,2,1 it can't be 1,2,3 or 3,1,2 or something like that?

The body method is called when m_Arrival->Activate() is executed, and it is running as an independent thread.