While I don't know the answer I suspect it is because Switch is actually a source filter and it probably isn't generated correct perl for the mod_perl environment. In fact, I quote from the module's documentation.

BUGSThere are undoubtedly serious bugs lurking somewhere in code this funky :-) Bug reports and other feedback are most welcome.
I'd almost rather just point you towards something else besides Switch if only because you're introducing such oddball code that I couldn't help but laugh when I read your introductory sentence.

In reply to Re: Switch (module) and Apache::Registry problem. by diotalevi
in thread Switch (module) and Apache::Registry problem. by jdtoronto

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