incorrect reprojection on windows (7), fine on linux

[nirvn]

There's an on the fly reprojection issue going on with QGIS on windows platform (working fine under linux, untested on mac).

On the windows version of QGIS, a WGS84 datum layer and its Indian 1960 48N datum equivalent fails to project on top of each other, ending up in a +450 meter (!) difference in location. (see screenshot attached)

I've been noticing this for quite some time but didn't find a good way to explain the issue until now.

Steps to reveal issue:

1. Create a new program, set the CRS to UTM Indian 1960 48N and activate on the fly reprojection.
2. Load the raster @ ​http://licadho-cambodia.org/qgis/ASTGTM_N11E103.zip (it's a simple aster gdem geotiff) into the project
3. Using the gdal's wrap tool, transform the astgm_n11e103_dem.tiff's WGS84 datum to Indian 1960 48N datum
4. Load the generated raster
5. Apply the this colormap (​http://licadho-cambodia.org/qgis/bugramp.txt) to both rasters to make it easier to observe the issue

Et voila.

Loading the two rasters into the linux version of QGIS will render just fine.