I'd love to help you with perlbrew, but I find it too complicated, for simple debug, try perl -V or perl -e " die $^X "

This works for me

download, make, install, perl 5.8.1

wget -c http://cpan.org/src/perl-5.8.1.tar.gz
tar -zxvf perl-5.8.1.tar.gz
cd perl-5.8.1
./Configure -des -Dprefix=~/p/5.8.1/
make install
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use this perl by making it first in path

export PATH=~/p/5.8.1/perl/bin:$PATH
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verify path

which perl
perl -V
perl -e "die $^X"
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verify path from cpanp

$ cpanp
CPANPLUS::Shell::Default -- CPAN exploration and module installation (
+v0.9105)
CPAN Terminal> !warn $^X
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