Any good way to align a tabular enviroment?

Is there any .el file using together with AUCTeX to align a tabular 
environment?

For example: Given a unformatted tabular environment
\begin{tabular}{lcr}
  a& b& 80\% \\
  \&& 55555&88\\
12345&        100       & 77
\end{tabular}

After using C-M-\, it can be aligned as following:
\begin{tabular}{lcr}
  a     & b     & 80\% \\
  \&    & 55555 & 88   \\
  12345 & 100   & 77
\end{tabular}
The elements can be aligned at &'s.

Any .el file or AUCTeX style can format a tabular nicely?  Thanks.



BTW: I'm using AUCTeX 11.55
                         MikTeX 2.4
                         CVS Emacs 21.3.50.1
                         Windows XP.
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Best Regards,
Adam