VS 2008 Debugger going crazy?

Look at the code below and put the breakpoint on line
if (_s == null)

observe the behavior when we do something like
s2 = Singleton.getSingletonInstance();

using System;

namespace Pattern
{
class Program
{
static void Main(string[] args)
{
Singleton s1, s2;

s1 = Singleton.getSingletonInstance();

s1.instanceCount = 100;

s2 = Singleton.getSingletonInstance();
}
}


sealed class Singleton
{
private static Singleton _s = null;
public int instanceCount;

private Singleton()
{
}

public static Singleton getSingletonInstance()
{
if (_s == null)
{
_s = new Singleton();
}

return _s;
}

}
}

When the breakpoint will hit, try watching the value of _s. The watch window will pop endlessly all over the screen when you click on the following + sign next to the static members icon.
Screenshot: