Exceptions failing in libstdc++

[red floyd]

G++ 3.2.3 (RedHat Enterprise Linux 3), x86

g++ --version returns:

g++ (GCC) 3.2.3 20030502 (Red Hat Linux 3.2.3-49)

Boiled down to essentials (and unfortunately, the minimun example won't 
barf), I have:


class X {
public:
  X() { /* ... */ };
  // ... etc etc...
};


void f()
{
    throw X();
}

void g()
{
 // yada yada yada
  try {
    f();
  }
  catch (X&)
  {
    // do something
  }

}


But when f() throws X as an exception, the program terminates,
and the libstdc++ code in __cxa_throw has a comment of:

    // Some sort of unwinding error.  Note that terminate is a handler.
    __cxa_begin_catch (&header->unwindHeader);
    std::terminate ();

The full-bore code in question works properly under VC7.1

GDB shows that the call to f() is occuring within a try/catch block, 
which catches X&.

I'm compiling with -pthread -fexceptions

Any suggestions?