CPAN distribution IO-Capture-Stdout-Extended has been superseded by IO-Capture-Extended, which subsumes IO-Capture-Stdout-Extended and adds IO-Capture-Stderr-Extended. The same methods which extended the functionality of IO-Capture-Stdout can now be used, without modification except for a change in the constructor, to extend the functionality of IO-Capture-Stderr. Incidentally, there's a new, improved version of IO-Capture (v0.05) out from author Mark Reynolds.