Core JavaScript 1.5 Reference:Global Objects:ReferenceError:constructor
From MDC
[edit] Summary
Returns a reference to the object's constructor.
[edit] Description
Returns a reference to the ReferenceError function that created the instance's prototype. The value of this property is a reference to the function itself, not a string containing the function's name. If this is desired, use the name property or the non-standard Function.prototype.name property.
Note that both an instance's constructor and name properties can be modified.