[GRASSLIST:1156] density surface from points in PostGIS

[uli]

Hi list

New to GRASS but with a pressing geostatistical task I hope for your help:

I have a PostGIS table with some hundreds of points (x,y, no other
attributes). I need to calculate the "density" of points within a given
radius for each cell of a grid. "Density" here simply means the number of
points, nothing like kernel or interpolations.
The output can be in GRASS format or PostGIS or anything else.

What is the fastset way to do this?
Do I need GRASS, or are you aware of any other more compact tools?
Or do you have an idea for a fast SQL-statement doing the job?

Thank you, Uli