Problem:
The \htmladdnormallinkfoot{text}{URL} command
fails when LaTeX is run if the URL contains an underscore
(or any other symbol LaTeX considers a 'mathematical' symbol).
Solution:
Use the \htmladdnormallink{text}{URL}
command instead. This produces a hyperlink when used in conjunction
with
latex2html, but does NOT try to produce a footnote
when used with LaTeX.