\makeatother
\newcommand{\cirnum}[1]{%
 \textcircled{%
 \ifthenelse{\equal{\f@size}{12}}{\small}{%
  \ifthenelse{\equal{\f@size}{10}}{\scriptsize}{%
   \ifthenelse{\equal{\f@size}{9}}{\tiny}{}%
   }%
  }%
 #1%
}
\makeatletter