Works for me:

> perl -MTime::Piece -wE "say $Time::Piece::VERSION; my $t=Time::Piece
+->strptime('05/10/1969','%m/%d/%Y'); say $t->ymd; say $t->strftime('%
+Y-%m-%d')"
1.20_01
1969-05-10
1969-05-10
[download]

> perl -v

This is perl 5, version 14, subversion 2 (v5.14.2) built for MSWin32-x
+86-multi-thread
[download]