This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
To override Object.equals(Object) in accordance with its contract, you need to do a little more.
Note that passing equals(Object) an argument that is null or is a different type is legal and returns false. This is different from compareTo(Object), which throws a ClassCastException if the argument is not the same type and a NullPointerException if the argument is null.
The equals method in your class needs to be implemented in order for it to make sense. By default, it doesn't contains any implementation, since you could have so many different kinds of objects & to test for equality, many require different criterias.
Hence, it is up to the developer to implement their own equals method if they wish to use it.
To make sense & see how to do it, read the Effective Java by Joshua Bloch. Sun had provided a few sample chapters & one of them shows to how to override a few important methods such as equals, hashCode, toString & clone.