[sigc] 2.0.10 completely breaks recursive signals

[Joseph Artsimovich <joseph tts lt>]

In the changelog for version 2.0.10 I see this:
* When signal handlers are connected made during an emit
  of the same signal, prevent them from being called in the
  same emit, to prevent infinite loops.

However it seems that this change completely breaks the ability to emit 
a signal recursively.
The following example illustrates the problem.  The expected behavior 
is that slot() to be called 4 times, but on 2.0.10 it gets called only 
once.  Note that I don't connect a slot during the signal emission.

#include <sigc++/sigc++.h>
#include <iostream>

class Test : public sigc::trackable
{
public:
	Test() : m_recursionLimit(4) {
		m_signal.connect(sigc::mem_fun(*this, &Test::slot));
	}
	
	void signal() { m_signal.emit(); }
	
	void slot() {
		std::cout << "slot" << std::endl;
		if (--m_recursionLimit > 0) {
			signal();
		}
	}
private:
	int m_recursionLimit;
	sigc::signal0<void> m_signal;
};

int main()
{
	Test test;
	test.signal();
}