augmentum in Gregorian notation compromises layout and is applied to wrong (groups of) notes

[Peter Sisak]

>I'm not top posting.
%% the augmentum command is applied to wrong notes (it is to be used as a 
prefix)
%% the layout is also compromised
%% the 3-4. lines demonstrate that the workaround suggested in the 
documentation also helps nothing,
%% just messes around the score layout even more
\include "gregorian.ly"
\score {
    \new VaticanaVoice {
      \augmentum {\[g\melisma\pes a\melismaEnd\]} \[g\melisma\pes 
a\melismaEnd\] \finalis
          \[g\melisma\pes a\melismaEnd\] \augmentum{\[g\melisma\pes 
a\melismaEnd\]} \finalis
      \augmentum {\[g\melisma\pes a\melismaEnd\]} \[g\melisma\pes 
a\melismaEnd\] s64 \finalis
          \[g\melisma\pes a\melismaEnd\] \augmentum{\[g\melisma\pes 
a\melismaEnd\]} s64 \finalis
    }
}