diff --git a/mcs/class/Microsoft.Build/Microsoft.Build.Evaluation/ProjectCollection.cs b/mcs/class/Microsoft.Build/Microsoft.Build.Evaluation/ProjectCollection.cs
index 21ca73594118f..45fa5f8bc70c5 100644
--- a/mcs/class/Microsoft.Build/Microsoft.Build.Evaluation/ProjectCollection.cs
+++ b/mcs/class/Microsoft.Build/Microsoft.Build.Evaluation/ProjectCollection.cs
@@ -348,9 +348,9 @@ static IEnumerable<T> GetWellKnownProperties<T> (Func<string,string,T> create)
 		{
 			var ext = Environment.GetEnvironmentVariable ("MSBuildExtensionsPath") ?? DefaultExtensionsPath;
 			yield return create ("MSBuildExtensionsPath", ext);
-			var ext32 = Environment.GetEnvironmentVariable ("MSBuildExtensionsPath32") ?? DefaultExtensionsPath;
+			var ext32 = Environment.GetEnvironmentVariable ("MSBuildExtensionsPath32") ?? ext;
 			yield return create ("MSBuildExtensionsPath32", ext32);
-			var ext64 = Environment.GetEnvironmentVariable ("MSBuildExtensionsPath64") ?? DefaultExtensionsPath;
+			var ext64 = Environment.GetEnvironmentVariable ("MSBuildExtensionsPath64") ?? ext;
 			yield return create ("MSBuildExtensionsPath64", ext64);
 		}