What do you see as Perl5's greatest limitation?

For me it's the lack of de-facto standard reliable encapsulation / information hiding mechanisms for OO code.

While there are many mechanisms that can get you decent encapsulation/information hiding they all suffer one or more of:

• Being more complicated that the "standard" hash mechanism.
• Relying on external CPAN modules
• Not work well with the other N methods of doing it