0.03 31 March 2012 Added some pod. Made sure it runs with 5.14.2, threaded and unthreaded. 0.02 4 December 2004 Added a real test-suite. Added THEORY OF OPERATION section, as well as documentation of all the new features. Added simple debugging output, activated with the OGD_DEBUG environment variable. Added configurable cleanup interval with OGD_CLEANUP environment variable. Fixed problem with cleanup interfering with weakening of references. 0.01 3 December 2004 First version of ogd.