My gdal is the latest version and compiled by myself, and tcltk
8.4 is apt-get from debian unstable version,isn't it work with grass
5.7?
I haven't tried in a while, but Tcl/Tk 8.4 would make NVIZ crash on startup.
probably a threading problem.
Need to build with the tcl8.3-dev and tk8.3-dev packages.
You can have tcl/tk 8.4 installed, just not the 8.4-dev packages.
Hamish