Description:
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Request: Add simple encryption support to serialize and unserialize.

Rationale: It is useful to be able to serialize an object and hide it in a form variable on a web page.  This is vulnerable to tampering by the end user.

serialize(mixed $value[, string $key])
unserialize(string $str[, string $key])

This new definition won't break existing code and could be implemented using a TEA variant in a few lines.  It would be nice if objects didn't have to be persisted in $_SESSION, because some power users want to use multiple windows to work with different objects simultaneously (editing two "invoice" objects at the same time, but commiting only complete changes of each).