Comment 4 for bug 913102

If it is off any help, here is a stab at a bbx file:

\ProvidesFile{moderncv.bbx}

\RequireBibliographyStyle{authortitle}

\defbibenvironment{bibliography}
  {\list
     {}
     {\setlength{\leftmargin}{6.5em}%
      \setlength{\itemindent}{0pt}%
      \setlength{\itemsep}{\bibitemsep}%
      \setlength{\parsep}{\bibparsep}}}
  {\endlist}
  {\item}

\endinput

And cbx:

\ProvidesFile{moderncv.cbx}

\RequireCitationStyle{authortitle}

\endinput

It is not really my field of programming, so it may be a bit "hacky".