[Proj] trying to understand results of reprojecting from epsg 4326 to epsg 31370

[Moritz Lennert]

On 07/07/09 16:56, Noel Zinn wrote:
> Consider changing the signs of the three rotations if you can do that 
> manually, or the rotation sense of the 7-parameter transformation.

That was it. Thanks also to Clifford for the same hint. Could someone 
explain the logic to me ? Why negate the translation, but not the 
rotation compared to the WGS84->Bel72 transformation ?

And: should the information linked to EPSG code 31370 be corrected ? How 
should I go about doing this ?

Moritz