diff --git a/src/OpenMesh/Core/Mesh/Handles.hh b/src/OpenMesh/Core/Mesh/Handles.hh
index 6cbb8ac4..68ac1d7e 100644
--- a/src/OpenMesh/Core/Mesh/Handles.hh
+++ b/src/OpenMesh/Core/Mesh/Handles.hh
@@ -165,8 +165,9 @@ namespace std {
 
 template <>
 struct hash<OpenMesh::BaseHandle >
-  : public std::unary_function<OpenMesh::BaseHandle, std::size_t>
 {
+  typedef OpenMesh::BaseHandle argument_type;
+  typedef std::size_t result_type;
 
   std::size_t operator()(const OpenMesh::BaseHandle& h) const
   {
@@ -176,8 +177,9 @@ struct hash<OpenMesh::BaseHandle >
 
 template <>
 struct hash<OpenMesh::VertexHandle >
-  : public std::unary_function<OpenMesh::VertexHandle, std::size_t>
 {
+  typedef OpenMesh::VertexHandle argument_type;
+  typedef std::size_t result_type;
 
   std::size_t operator()(const OpenMesh::VertexHandle& h) const
   {
@@ -187,9 +189,11 @@ struct hash<OpenMesh::VertexHandle >
 
 template <>
 struct hash<OpenMesh::HalfedgeHandle >
-  : public std::unary_function<OpenMesh::HalfedgeHandle, std::size_t>
 {
 
+  typedef OpenMesh::HalfedgeHandle argument_type;
+  typedef std::size_t result_type;
+  
   std::size_t operator()(const OpenMesh::HalfedgeHandle& h) const
   {
     return h.idx();
@@ -198,9 +202,11 @@ struct hash<OpenMesh::HalfedgeHandle >
 
 template <>
 struct hash<OpenMesh::EdgeHandle >
-  : public std::unary_function<OpenMesh::EdgeHandle, std::size_t>
 {
 
+  typedef OpenMesh::EdgeHandle argument_type;
+  typedef std::size_t result_type;
+  
   std::size_t operator()(const OpenMesh::EdgeHandle& h) const
   {
     return h.idx();
@@ -209,9 +215,11 @@ struct hash<OpenMesh::EdgeHandle >
 
 template <>
 struct hash<OpenMesh::FaceHandle >
-  : public std::unary_function<OpenMesh::FaceHandle, std::size_t>
 {
 
+  typedef OpenMesh::FaceHandle argument_type;
+  typedef std::size_t result_type;
+  
   std::size_t operator()(const OpenMesh::FaceHandle& h) const
   {
     return h.idx();