GROMACS

Sometime in 2013 during the master branch development a bug was introduced that makes that the coordinates of vsiten particles are not integrated, that is they remain at the same position. In the attached example one has to change the particle type of the MW particle in amber99sb-ild.ff/ffnonbonded.itp to V (or D) to make it work, then

grompp -maxwarn 20
mdrun

gmx gmxdump -f traj.xtc | grep ' 1100\]'
x[ 1100]={ 5.35100e+00, 6.43100e+00, 5.72700e+00}
x[ 1100]={ 5.35100e+00, 6.43100e+00, 5.72700e+00}
x[ 1100]={ 5.35100e+00, 6.43100e+00, 5.72700e+00}
x[ 1100]={ 5.35100e+00, 6.43100e+00, 5.72700e+00}
x[ 1100]={ 5.35100e+00, 6.43100e+00, 5.72700e+00}

As you see the coordinates of this vsiten particle is exactly constant!
It works fine in 4.6 and earlier, as well as in older master branches. I tried git bisect but could not find the right position :(.