Segfaulting polymorphism (Suspected stack corruption - Code on github)

Question

It's a little difficult to explain the offending piece of code, as there seems to be some degree of stack corruption, and all the code's pretty linked together (it's a game). If you're looking for a headache and some debugging, please check out the segfault branch on git://github.com/RobotGymnast/Gingerbread.git and see if you can find what's causing the stack corruption/segfault. I marked my suspect with a #error

Here's the offending code (I think):

void Update()
{
    // TODO: only check those that have moved
    for(PhysicsObjectList::iterator collider = objects.begin(); collider != objects.end(); ++collider)
    {
        PhysicsObjectList::iterator collidee = collider;
        ++collidee;
        for(PhysicsObjectList::iterator end = objects.end(); collidee != end; ++collidee)
        {
            if(IsCollide(**collider, **collidee))
            {
                #error commenting out code below stops segfaults
                (*collider)->CollisionHandler(*collidee);
                (*collidee)->CollisionHandler(*collider);
            }
        }
    }
}

WorldObject:

 class WorldObject
    {
    public:

        Point location;
        size_t height, width;

        virtual ~WorldObject();

        virtual ObjectType GetObjectType() const = 0;
        virtual void CollisionHandler(const WorldObject* colidee) = 0;
    };

Hmm.. the code doesn't seem to be displaying properly.