What Perl did you use?
The OP's code works fine for me with:
5.8.4 on FreeBSD
5.6.0 on WinXP (ActivePerl build 623)
5.6.1 on WinXP (ActivePerl build 635)
5.8.0 on WinXP (ActivePerl build 806)
5.8.8 on WinXP (ActivePerl build 817)
5.10.0 on WinXP (ActivePerl build 1001)

In reply to Re^4: encryption golf (one time pad) by ikegami
in thread encryption golf (one time pad) by mr_mischief

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