[help-texinfo] pdf links can not understand underscore ("_")

[Jinsong Zhao]

Hi there,

In a manual, I use the following code with XeTeX to create links for 
cross-reference. If the #1 contains an underscore ("_"), the link 
generated dose not work.

Sorry for no minimal example. You can refer to 
http://maxima.sourceforge.net/docs/manual/maxima.pdf, page 27, for 
example, ``kill'' and ``run_testsuite'' in green color. They are make 
with the same command. However, the ``kill'' link works, but 
``run_testsuite'' does not work.

\def\mmref#1#2{%
  {\leavevmode%
   \special{pdf:bann << /Border [0 0 0] /Type /Annot /Subtype /Link /A
         << /S /GoTo /D (#1) >> >>}%
  }%
  \setcolor{\linkcolor}%
  #2%
  \endlink%
}

The above code is steal from the latest texinfo.tex. Any suggestion will 
be really appreciated.

BTW, is it possible to create a cross-reference without pages. The @ref, 
@xref, or @pxref all have pages in the final output. I just hope to 
cross refer to a node with color pdf links.

Best,
Jinsong