[Proj] question about rotation

[Roman Kazmin]

Hi anybody.
I'm beginner in LibProjj4. I have coordinate system and the following 
parameters:
sprintf(strProj, "+proj=stere +ellps=WGS84 +lat_0=%.9f +lon_0=%.9f 
+units=m", lat1, lon1)
FalseEasting   = 0;
FalseNorthing = 0;
Besides there is one parameter with which I do not know what to do. It 
is orientation. As I know it decsribes the orientation of the grid 
i.e., the east longitude value of the meridian which is parallel to 
the y-axis (or columns of the grid) along which latitude increases as 
the y-coordinate increases.
I want to receive transformation of coordinates from given to latitude 
and a longitude.
Thanks all.