latex fragment problems with * environments

[Eric S Fraga <e.fraga@ucl.ac.uk>]

Carsten et al.,

If I have the following bit of LaTeX code in my org file:

,----
|   \begin{eqnarray}
|     x &=& a_i + b_j + c_{k} \\
|     y &=& \sqrt{x}
|   \end{eqnarray}
| 
|   \begin{eqnarray*}
|     x &=& a_i + b_j + c_{k} \\
|     y &=& \sqrt{x}
|   \end{eqnarray*}
`----

and ask for a LaTeX export, I get the following generated:

,----
|   \begin{eqnarray}
|     x &=& a_i + b_j + c_{k} \\
|     y &=& \sqrt{x}
|   \end{eqnarray}
| 
|   \begin{eqnarray*}
|     x \&=\& a$_i$ + b$_j$ + c$_{k}$ \\
|     y \&=\& \sqrt{x}
|   \end{eqnarray*}
`----

The second environment has not been recognised by org-mode as a valid
latex fragment and so all the special characters (&, _) have been
processed instead of being left alone.  

This could be my fault but I have no idea where to start looking in case
I've set something I shouldn't have.  Because the latex exporter has
changed since I last used any latex fragments in my org files, and that
has been a while, I am not sure if this ever worked properly anyway.

Or it could be that "*" environments don't get recognised correctly by
the latex exporter?  Is there a regexp that I can customise for this?

Thanks for any suggestions!  I've temporarily changed all * environments
to ones with the * (so I get tons of equation numbers I don't need) but
I would love to revert to what I had originally.

eric