Hi, since nobody took care of this issue, I took the liberty to fix this bug and upload directly on unstable, due to policy allowing to put on 0 day queue packages with more than 7 days old RC bugs and no intention to fix.
I did upload as NMU, even if I'm in the Debian Science team, because I would like to avoid maintaining this package, and switch ASAP to vtk6. This is unfortunately still needed to make the netcdf transition finish, and I guess I'll try to move to vtk-5.10 in the near future, at least to avoid loosing all the work I did for the vtk-5.10 version. BTW In order to avoid a new transition for tcl/tk 8.5 removal, I took the liberty to cherry-pick the ubuntu 8.6 patch, specially because we are already transitioning due to the v5 soname change. I hope it is ok, I don't think tcl-tk 8.5 will be still there for Stretch (and I hope also vtk won't be there) cheers, Gianfranco