Numbering and cross-references

Question

I am writing a large document (guess what) with chapter, section, subsection, subsubsection (and paragrph).

I have changed the numbering to fit my taste:

\setcounter{secnumdepth}{3} % Number subsubsections
\def\thechapter       {\Roman{chapter}}
\def\thesection       {\arabic{section}}
\def\thesubsection    {\thesection.\arabic{subsection}}
\def\thesubsubsection {\thesubsection.\arabic{subsubsection}}

This is nice but I have a problem. Suppose that in chapter II, I write a reference to section I.2. It will be rendered as 2 (ie, no chapter information).

Is there a way to deal with that?

Thanks in advance.

P.S.: for details I use hyperref (the link points to the right section) and autoref.

Answer 1

Add the reference prefix, which is printed just before the label value, manually:

\makeatletter
\renewcommand{\p@section}{\thechapter.}
\makeatother