Is java object serialization compatible between 1.5 and 1.6

Question

I am wondering whether it is safe to mix jdk 1.5 and 1.6 (Java 6) object serialization (biderctional communication). I searched for an explicit statement from sun concerning

Answer 1

The serialization mechanism in 1.5 and 1.6 is compatible. Thus, the same code compiled/running in a 1.5 and 1.6 context can exchange serialized objects. Whether the two VM instances have the same/compatible version of the class (as may be indicated by the serialVersionUID field) is a different question not related to the JDK version.

If you have one serializable Foo.java and use this in a 1.5 and 1.6 JDK/VM, serialized instances of Foo created by one V; can be deserialized by the other.