I don't think any of them will have any issues except possibility differences in warnings for bad data.

I know that pack changed how it handled some invalid inputs, but that's not relevant here.

Upd: Looks like you found a possible source of problems: Incompatibility after perl 5.10 packing and UTF-8 strings

In reply to Re: pack unpack incompatibility issue by ikegami
in thread Incompatibility after perl 5.10 packing and UTF-8 strings by powerperl

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