Release Notes: This release fixes a double free() in the error handling classes by moving the error classes to a smart pointer framework similar to the remainder of the library. Errors thrown are now smart pointer instances of error objects. This keeps the syntax for errors inline with the other smart pointers used throughout dbus-cxx. This means that boolean tests such as "if (error) ..." are not valid. The test would need to examine the is_set() method of an error smart pointer as in "if (error->is_set()) ...". Also, a logic error in CallMessage::expects_reply() was fixed.