stopping a boost::thread

Hi everyone,

I am trying to use the boost multithreading library. I am having a
problem as the join() function for the thread never returns. I am using
a boolean variable to indicate when the thread should stop running.
Here is basically a stub of what I am doing:
Code:

//........................................
bool m_RunThread = false;
scoped_ptr<boost::thread> myThread;
//.......................................

void MyObject::StartThread()
{
m_RunThread = true;
myThread.reset(new boost::thread(boost::bind
(&MyObject::MyThreadFunc, this)));

}

void MyObject::StopThread()
{
m_RunThread = false;
myThread.join(); // this function never returns!

... Never gets here....
}

void MyObject::MyThreadFunc()
{
while (m_RunThread)
{
// do something
}
}
However, the join() function in StopThread never returns. I think that
using a variable to synchronize this is probably not a good idea. Any
thoughts and suggestions?

Cheers,
xargy