Melisma and underscores

[Nancho Alvarez]

Hi
I would like to know if there is any way to indicate a melisma using the 
underscore _ (or other character) inside the Lyrics block.
I know that to get a melisma the proper thing to do is combine the lines:

\notes{c \melisma d e f \melismaEnd g}
\lyrics{li -- ly -- pond }

but I would like to use something similar to

\notes{c d e f g }
\lyrics{li -- _ _ ly -- pond }




I have written some lilypond files with music by Tomas Luis de Victoria 
(http://tomasluisdevictoria.org),
using this erroneus syntax because I thought it was correct.
The problem of this approach is that the hypens are not properly 
displayed nor the alignment is correct.
I tried to adapt it to the good syntax but it is a great lot of work,
there are more than 200 files and it is music very melismatic and with 
many different voices.
For that reason, my last hope is that there exist a variable o property 
to force lilypond to understand  the underscores as
melisma and treat them as if there were a pair \melisma \melismaEnd 
inserted.
Thank you in advance
                                             NANCHO