diff --git a/Circular_kernel_2/Benchmarks/DxfArrayBenchmarks/benchmarks_arrangement.C b/Circular_kernel_2/Benchmarks/DxfArrayBenchmarks/benchmarks_arrangement.cpp
similarity index 100%
rename from Circular_kernel_2/Benchmarks/DxfArrayBenchmarks/benchmarks_arrangement.C
rename to Circular_kernel_2/Benchmarks/DxfArrayBenchmarks/benchmarks_arrangement.cpp
diff --git a/Circular_kernel_2/Benchmarks/arrangement_traits/benchmarks_arrangement.C b/Circular_kernel_2/Benchmarks/arrangement_traits/benchmarks_arrangement.cpp
similarity index 100%
rename from Circular_kernel_2/Benchmarks/arrangement_traits/benchmarks_arrangement.C
rename to Circular_kernel_2/Benchmarks/arrangement_traits/benchmarks_arrangement.cpp
diff --git a/Circular_kernel_2/Benchmarks/arrangement_traits/benchmarks_arrengement_traits.C b/Circular_kernel_2/Benchmarks/arrangement_traits/benchmarks_arrengement_traits.cpp
similarity index 100%
rename from Circular_kernel_2/Benchmarks/arrangement_traits/benchmarks_arrengement_traits.C
rename to Circular_kernel_2/Benchmarks/arrangement_traits/benchmarks_arrengement_traits.cpp
diff --git a/Circular_kernel_2/Benchmarks/benchmark_CK2.C b/Circular_kernel_2/Benchmarks/benchmark_CK2.cpp
similarity index 100%
rename from Circular_kernel_2/Benchmarks/benchmark_CK2.C
rename to Circular_kernel_2/Benchmarks/benchmark_CK2.cpp
diff --git a/Circular_kernel_2/Benchmarks/benchmarks_arrangement.C b/Circular_kernel_2/Benchmarks/benchmarks_arrangement.cpp
similarity index 100%
rename from Circular_kernel_2/Benchmarks/benchmarks_arrangement.C
rename to Circular_kernel_2/Benchmarks/benchmarks_arrangement.cpp
diff --git a/Circular_kernel_2/Benchmarks/bff_reader/Breader.C b/Circular_kernel_2/Benchmarks/bff_reader/Breader.cpp
similarity index 100%
rename from Circular_kernel_2/Benchmarks/bff_reader/Breader.C
rename to Circular_kernel_2/Benchmarks/bff_reader/Breader.cpp
diff --git a/Circular_kernel_2/Benchmarks/dxf_to_bff/converter.C b/Circular_kernel_2/Benchmarks/dxf_to_bff/converter.cpp
similarity index 100%
rename from Circular_kernel_2/Benchmarks/dxf_to_bff/converter.C
rename to Circular_kernel_2/Benchmarks/dxf_to_bff/converter.cpp
diff --git a/Circular_kernel_2/Benchmarks/incremental_insertion/benchmarks_arrangement.C b/Circular_kernel_2/Benchmarks/incremental_insertion/benchmarks_arrangement.cpp
similarity index 100%
rename from Circular_kernel_2/Benchmarks/incremental_insertion/benchmarks_arrangement.C
rename to Circular_kernel_2/Benchmarks/incremental_insertion/benchmarks_arrangement.cpp
diff --git a/Circular_kernel_2/Benchmarks/makefile b/Circular_kernel_2/Benchmarks/makefile
index 63d52affd37..0747d1d22e6 100644
--- a/Circular_kernel_2/Benchmarks/makefile
+++ b/Circular_kernel_2/Benchmarks/makefile
@@ -13,9 +13,6 @@
            #-DCGAL_PROFILE \
            #-g
 
-CGAL_MAKEFILE =/proj/geometrica/home/CGAL/CGAL-I/make/makefile_i686_Linux-2.6_g++-4.0.2
-#makefile_i686_Linux-2.6_g++-3.4.4
-
 include $(CGAL_MAKEFILE)
 
 
@@ -64,6 +61,6 @@ clean: \
 #                    suffix rules
 #---------------------------------------------------------------------#
 
-.C$(OBJ_EXT):
+.cpp$(OBJ_EXT):
 	$(CGAL_CXX) $(CXXFLAGS) $(OBJ_OPT) $<
 
diff --git a/Circular_kernel_2/Benchmarks/parser/benchmark_lexer.C b/Circular_kernel_2/Benchmarks/parser/benchmark_lexer.cpp
similarity index 100%
rename from Circular_kernel_2/Benchmarks/parser/benchmark_lexer.C
rename to Circular_kernel_2/Benchmarks/parser/benchmark_lexer.cpp
diff --git a/Circular_kernel_2/Benchmarks/parser/benchmark_parser.C b/Circular_kernel_2/Benchmarks/parser/benchmark_parser.cpp
similarity index 100%
rename from Circular_kernel_2/Benchmarks/parser/benchmark_parser.C
rename to Circular_kernel_2/Benchmarks/parser/benchmark_parser.cpp
diff --git a/Circular_kernel_2/Benchmarks/parser/benchmark_visitor.C b/Circular_kernel_2/Benchmarks/parser/benchmark_visitor.cpp
similarity index 100%
rename from Circular_kernel_2/Benchmarks/parser/benchmark_visitor.C
rename to Circular_kernel_2/Benchmarks/parser/benchmark_visitor.cpp