diff --git a/tests/xharness/WatchOSTarget.cs b/tests/xharness/WatchOSTarget.cs
index 83b7cea02b..468cf36771 100644
--- a/tests/xharness/WatchOSTarget.cs
+++ b/tests/xharness/WatchOSTarget.cs
@@ -72,7 +72,7 @@ namespace xharness
 			csproj.FixArchitectures ("i386", "ARMv7k");
 			csproj.FixInfoPListInclude (suffix);
 			csproj.SetOutputType ("Library");
-			csproj.AddAdditionalDefines ("XAMCORE_2_0;XAMCORE_3_0");
+			csproj.AddAdditionalDefines ("XAMCORE_2_0;XAMCORE_3_0;FEATURE_NO_BSD_SOCKETS");
 			csproj.RemoveReferences ("OpenTK");
 			var ext = IsFSharp ? "fs" : "cs";
 			csproj.AddCompileInclude ("InterfaceController." + ext, Path.Combine (Harness.WatchOSExtensionTemplate, "InterfaceController." + ext));