Version 0.2:
	The frozen info starts with 'FrT;'. Warning if not - nonfatal.
	Results of freezeEmpty are cached, explanation about caching
FreezeEmpty added.
	At last, all the tests are OK.
	Little bit more compact backreferences.
Version 0.2:
	New tests added and work.
	"Repeated" handled much cleaner now (basing on $secondpass).
	Packages are stored in a more compact form.
	Numbers are stored in a more compact form.
Version 0.4:
	Can handle overloaded objects.
Version 0.41:
	Bug in detecting duplicated overloaded objects fixed.
	(When Reissued:)
	Remove wrong comments on faking out tests in t/*.
	Add a POD section on limitations.
Version 0.42:
	Fix test for a change of string representation of Math::BigInt.
	Support qr// objects (via UNIVERSAL, so if Regexp supports
		(de)serialization methods, they will be used instead).
	`use strict'-complient.
Version 0.43:
	Correct save/restore of overloaded values, including repeated refs.