WMS server returns wrong BoundingBox for PostGIS layers

[nikita.shulga@…]

LayerGetExtent function for PostIGIS layers is dummy function(defined in mappostgis.c) always returns (-
MAXFLOAT,-MAXFLOAT,MAXFLOAT,MAXFLOAT), so layer extent for PostGIS-layer is not specified in .map-
file one will get enormously large BoundingBox and LatLonBoundingBox as reply to 
GetCapabilitiesRequest...
All one have to do to fix it is to issue following query "select extent(%geometry_column%) from %
table_name% %filter%" to PostGIS DB and parse its results.. This code is already present in mappostgis.c 
but it disabled because, as commentary to function said, "Never seen this function actually called"