siunitx: Detecting \mathversion{sans}

Is there a way to tell siunitx to use the \mathversion{sans} font in the following example?

\documentclass{scrartcl}
\usepackage[T1]{fontenc}
\usepackage{helvet}
\renewcommand\familydefault{\sfdefault}
\usepackage{sansmath}
\usepackage{siunitx}
\begin{document}
\mathversion{sans}
$1=1 \SI{1}{\meter}$

\end{document}


(\sisetup{mode=text} is cheating).

-

Not a 'detection' issue here: the problem is some code siunitx uses to try to avoid 'accidentally' making things bold. Try for example

\documentclass{scrartcl}
\usepackage[T1]{fontenc}
\usepackage{helvet}
\renewcommand\familydefault{\sfdefault}
\usepackage{sansmath}
\usepackage{siunitx}
\makeatletter
\newcommand{\mymathversion}[1]{%
\mathversion{#1}%
\def\unboldmath{%
\@nomath\unboldmath
\mathversion{#1}%
}%
}
\makeatother
\begin{document}
\mymathversion{sans}
$1=1 \SI{1}{\meter}$

\end{document}

-
Note: I'm currently working on some code which may become siunitx version 3. Things like the treatment of bold math mode are important questions to think about: this is a useful case to consider! – Joseph Wright Mar 7 '14 at 16:34
Thanks, it was quite bewildering that siunitx insisted to use a roman font ;-). – Ulrike Fischer Mar 7 '14 at 16:52