Centering lyrics under melisma

[Marek Klein]

Hi,
is there simple way to center lyrics under whole melisma?

What I want to get is here:
<http://gregoriana.sk/wordpress/wp-content/uploads/centering_melisma1.png
>
What I get is here:
<http://gregoriana.sk/wordpress/wp-content/uploads/centering_melisma2.png>

Source:
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\version "2.10.25"
mb = \melisma
me = \melismaEnd

TextSchola= \lyricmode {
    Ma -- gni -- ficat anima me -- a Do -- mi -- num.
}

\score {
<<
\new Voice = "schola" \with {\remove "Time_signature_engraver" }
{
    \key f \major
    \set Score.timing = ##f
    \clef "G_8"
    f4 g128 \mb a4 \me a\breve
    \bar "|" 
    a\breve g4 f g128 \mb a4 \me g4 g128 \mb f e d4 \me
    \bar "|."
}
\new Lyrics \lyricsto "schola" \TextSchola
>>
\layout { raggedright = ##t
    \context {
      \Voice
      \remove "Stem_engraver"
      \remove "Phrasing_slur_engraver"
      \remove "Slur_engraver"
      \remove "Script_engraver"
      \remove "Beam_engraver"
      \remove "Auto_beam_engraver"
    }
}
}


Thanks.

Marek Klein,
Slovakia
http://gregoriana.sk