A trick like the following one allows a compilation to choose
between a pdf and a html mode automatically.
\ifx \HCode\UnDef \usepackage[pdf]{hyperref}
\else \usepackage[tex4ht]{hyperref} \fi
The trick assumes the compilations for html are invoked by
htlatex-like commands.
\Configure{::#1}
\Configure{::action}
\Configure{::default}
\Configure{::menulength}
\Configure{::method}
\Configure{::name}
\Configure{::value}
\Configure{CheckBox::checked}
\Configure{CheckBox::}
\Configure{ChoiceMenu::combo}
\Configure{ChoiceMenu::popdown}
\Configure{ChoiceMenu::radio}
\Configure{ChoiceMenu::}
\Configure{Form}
\Configure{PushButton::}
\Configure{Reset::}
\Configure{Submit::}
\Configure{TextField::default}
\Configure{TextField::multiline}
\Configure{TextField::password}
\Configure{TextField::width}
\Configure{TextField::}
\Configure{combo::default}
\Configure{multiline::value}
\Configure{multiline::width}
\Configure{radio::default}
-_-_-