diff --git a/bindings/python/mapnik_projection.cpp b/bindings/python/mapnik_projection.cpp
index cddbd5f82..22e8bfa0b 100644
--- a/bindings/python/mapnik_projection.cpp
+++ b/bindings/python/mapnik_projection.cpp
@@ -89,13 +89,10 @@ void export_projection ()
 {
     using namespace boost::python;
 
-    class_<projection>("Projection", "Represents a map projection.",init<optional<std::string const&> >(
+    class_<projection>("Projection", "Represents a map projection.",init<std::string const&>(
                            (arg("proj4_string")),
                            "Constructs a new projection from its PROJ.4 string representation.\n"
                            "\n"
-                           "The parameterless version of this constructor is equivalent to\n"
-                           "   Projection('+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs')\n"
-                           "\n"
                            "The constructor will throw a RuntimeError in case the projection\n"
                            "cannot be initialized.\n"
                            )
diff --git a/include/mapnik/projection.hpp b/include/mapnik/projection.hpp
index addd99e46..e7c846bee 100644
--- a/include/mapnik/projection.hpp
+++ b/include/mapnik/projection.hpp
@@ -48,7 +48,7 @@ class MAPNIK_DECL projection
     friend class proj_transform;
 public:
 
-    explicit projection(std::string const& params = MAPNIK_LONGLAT_PROJ,
+    projection(std::string const& params,
                         bool defer_proj_init = false);
     projection(projection const& rhs);
     ~projection();
diff --git a/tests/cpp_tests/geometry_converters_test.cpp b/tests/cpp_tests/geometry_converters_test.cpp
index a549f9aa2..b624676da 100644
--- a/tests/cpp_tests/geometry_converters_test.cpp
+++ b/tests/cpp_tests/geometry_converters_test.cpp
@@ -7,6 +7,7 @@
 #include <mapnik/vertex_converters.hpp>
 #include <mapnik/geometry.hpp>
 #include <mapnik/wkt/wkt_factory.hpp>
+#include <mapnik/well_known_srs.hpp>
 
 #if BOOST_VERSION >= 104700
 #include <mapnik/util/geometry_to_wkb.hpp>
@@ -46,8 +47,8 @@ boost::optional<std::string> linestring_bbox_clipping(mapnik::box2d<double> bbox
 {
     using namespace mapnik;
     agg::trans_affine tr;
-    projection src;
-    projection dst;
+    projection src(MAPNIK_LONGLAT_PROJ);
+    projection dst(MAPNIK_LONGLAT_PROJ);
     proj_transform prj_trans(src,dst);
     line_symbolizer sym;
     CoordTransform t(bbox.width(),bbox.height(), bbox);
@@ -86,8 +87,8 @@ boost::optional<std::string> polygon_bbox_clipping(mapnik::box2d<double> bbox,
 {
     using namespace mapnik;
     agg::trans_affine tr;
-    projection src;
-    projection dst;
+    projection src(MAPNIK_LONGLAT_PROJ);
+    projection dst(MAPNIK_LONGLAT_PROJ);
     proj_transform prj_trans(src,dst);
     polygon_symbolizer sym;
     CoordTransform t(bbox.width(),bbox.height(), bbox);