Quote 5.8.8's INSTALL:

Starting from Perl 5.8, the default mechanism is to use the PerlIO abstraction, because it allows better control of I/O mechanisms, instead of having to work with (often, work around) vendors' I/O implementations.

This PerlIO abstraction can be (but again, unless you know what you are doing, should not be) disabled either on the Configure command line with

sh Configure -Uuseperlio
[download]

or interactively at the appropriate Configure prompt.

You appear to be overriding the default somehow.