> Using l2h98.2b6, this file illustrates the problem
>
> \documentclass{article}
> \usepackage{alltt,html}
> \newenvironment{myalltt}{\begin{alltt}}{\end{alltt}}
>
> \newcommand{\foo}{\ \htmladdimg{../return.gif}\ }
>
> \begin{document}
> \begin{myalltt}
> one line \foo
> another line \foo
> and a third \foo
> \end{myalltt}
> \end{document}
>
Verbatim-like environments should not/cannot be redefined, for instance
you cannot do (even in LaTeX)
\newenvironment{myverbatim}{\begin{verbatim}}{\end{verbatim}}
The same is true with a lot of the amslatex display environments.
Therefore, the easiest thing is to use the "naked" environment in such
cases, and use an editor to expand your custom abbreviations, if that
is the reason why you want to redefine these environments.
Michel Goossens