[Orgmode] Two questions about latex export

[Robert Goldman]

1.  I am making a table of conditional probabilities.  This means the
table headers look like this: p(e|\omega), for example.  The vbar in the
header confuses orgmode.  It thinks that's a column-delimiter.  Adding a
prefix \ does not help.  Is there a work around?  For the moment I put
\newcommand{\vbar}{|} in a latex block and use \vbar in place of |.
Works, but makes the table a little less readable than I'd like.

more importantly:

2.  I put an eqnarray* environment in my org file.  The equation breaks
across multiple lines so it looks like this:

\begin{eqnarray*}

x &=& blah blah blah \\
  &=& blah blah blah \\
    &=& blah blah blah \\
\end{eqnarray*}

org-mode quotes (backslashes) the &=& so they don't get interpreted
correctly.  Is there something I can do to keep that from happening?

thanks!
Robert