[tex-k] Latex bug with eqnarray*

[Kevin S. Van Horn]

I have the following in a .tex file:

\begin{eqnarray*}
  p(\overline{x} \mid \mu, \sigma)
  & \propto &
  \sigma^{-1} \exp\left(-\frac{n}{2\sigma^2}(\overline{x}-\mu)^2\right) \\

  2 + 2 & = & 4
\end{eqnarray*}

LaTex gives an error on the blank line following "\\", saying "Missing $ 
inserted".  If I remove the blank line, everything is OK.

Doing "latex -version" gives

TeX (Web2C 7.4.5) 3.14159
kpathsea version 3.4.5

I am running the Libranet Linux 2.8.1 package.