I use lyx for writing webpages with math. I have \usepackage{html} in the preamble, and some documents starts with the following code
\begin{rawhtml} <?php include("../../lek_header.php") ?> \end{rawhtml} 1.2.0pre3 makes 3 ERT insets, which is fine - but also insists that the first of these inset is in the english language. I don't think that makes a difference, but it is certainly odd. The whole document used to be in norwegian. (\language norsk) The lyx file now have \lang english before the first inset, and it appears with a blue underline on screen. There is no trace of english in the pre-1.2.0pre3 file. Also, latex2html is much better at creating text math (instead of images) from the latex output by 1.1.6fix4 than the math output by 1.2.0pre3. I guess that is a latex2html problem though. Text math generally looks better than images. Helge Hafting