Use of marginpar: problems with Underfull \hbox

I'm using the latex commnad \marginpar{}, however for some reason I get the warning:

Underfull \hbox <badness 10000> in paragraph ...

each time I create a comment on the margin. Is there any way to avoid this?

This is how I use \marginpar{}:

\setlength{\marginparwidth}{1.2in}
\let\oldmarginpar\marginpar\reversemarginpar
\renewcommand\marginpar[1]{\-\oldmarginpar[\footnotesize #1]  {\raggedright\footnotesize #1}}

How could I modify the above? I read that \makebox[0pt]{} might help - but don't understand how?

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make a complete example, I do not get an underfull hbox –  Herbert Oct 6 '11 at 10:30