Does shapeobj->union exist in php-mapscript

[Paul Moen]

I get the following error.

    PHP Fatal error:  Call to undefined method ms_shape_obj::Union()

By doing the following.

    $wktshp1 = ms_shapeObjFromWkt($wkt1);
    $wktshp2 = ms_shapeObjFromWkt($wkt2);
    
    $newshp = $wktshp1->Union($wktshp2);

PHP/Mapscript docs say.
shapeobj Union(shapeobj shape)
        Returns a shape object representing the union of the current
        shape object with the one passed as parameter.
        Only available if php/mapscript is built with GEOS
        library.

GEOS is built in.
MapServer version 4.10.2 OUTPUT=GIF OUTPUT=PNG OUTPUT=JPEG OUTPUT=WBMP
OUTPUT=PDF OUTPUT=SWF OUTPUT=SVG SUPPORTS=PROJ SUPPORTS=FREETYPE
SUPPORTS=WMS_SERVER SUPPORTS=WMS_CLIENT SUPPORTS=WFS_SERVER
SUPPORTS=WFS_CLIENT SUPPORTS=WCS_SERVER SUPPORTS=SOS_SERVER SUPPORTS=GEOS
INPUT=EPPL7 INPUT=POSTGIS INPUT=OGR INPUT=GDAL INPUT=SHAPEFILE

Does union exist in PHP/Mapscript?

Thanks,

Paul