When reading documents containing the non-equal symbol, the diagonal bar is
not shown, and thus the non-equal symbol looks just like the equals symbol.

The rendering problems shows up in gpdf (cvs), but _not_ in ggv or xpdf.

Below: contents of test.tex, and use pdflatex to get text.pdf which shows
the abovementioned behaviour.

--------------------------
\documentstyle{letter}
\begin{document}

equals: $=$

does not equal: $\neq$

\end{document}
--------------------------