Spatial.Net Cartesian won't find docs in radius in certain cases

To replicate change Lucene.Net.Contrib.Spatial.Test.TestCartesian to the following witch should return 3 results.

Line
42: private double _lat = 55.6880508001;
43: private double _lng = 13.5871808352; // This passes: 13.6271808352

73: AddPoint(writer, "Within radius", 55.6880508001, 13.5717346673);
74: AddPoint(writer, "Within radius", 55.6821978456, 13.6076183965);
75: AddPoint(writer, "Within radius", 55.673251569, 13.5946697607);
76: AddPoint(writer, "Close but not in radius", 55.8634157297, 13.5497731987);
77: AddPoint(writer, "Faar away", 40.7137578228, -74.0126901936);

130: const double miles = 5.0;

156: Console.WriteLine("Distances should be 3 " + distances.Count);
157: Console.WriteLine("Results should be 3 " + results);

159: Assert.AreEqual(3, distances.Count); // fixed a store of only needed distances
160: Assert.AreEqual(3, results);