one of the documented procedures in this installation of the ACS
util_quotehtml   arg
What it does:
This procedure should be used instead of ns_quotehtml or philg_quote_double_quotes (at least in new scripts) because there is no case where one would want to quote only a subset of the four special HTML characters and not quote the rest.
Defined in: /web/philip/packages/acs-core/utilities-procs.tcl

Source code:

    regsub -all & $arg \\&amp\; arg
    regsub -all \" $arg \\&quot\; arg
    regsub -all < $arg \\&lt\; arg
    regsub -all > $arg \\&gt\; arg
    return $arg