diff --git a/cmake/SC_Paths.cmake b/cmake/SC_Paths.cmake
index 1a32525f..29f1a81f 100644
--- a/cmake/SC_Paths.cmake
+++ b/cmake/SC_Paths.cmake
@@ -1,32 +1,44 @@
-macro(REVERSE_PATH in_path out_path)
+macro(REVERSE_PATH in_path out_path drive_path)
   set(reversed_path)
   set(tmp_subpath "${in_path}")
   while(NOT "${tmp_subpath}" STREQUAL "" AND NOT "${tmp_subpath}" STREQUAL "/")
       get_filename_component(piece "${tmp_subpath}" NAME)
       get_filename_component(tmp_subpath "${tmp_subpath}" PATH)
-      set(reversed_path "${reversed_path}/${piece}")
+      if(piece)
+	set(reversed_path "${reversed_path}/${piece}")
+      else(piece)
+	set(${drive_path} ${tmp_subpath})
+	set(tmp_subpath)
+      endif(piece)
   endwhile(NOT "${tmp_subpath}" STREQUAL "" AND NOT "${tmp_subpath}" STREQUAL "/")
   set("${out_path}" "${reversed_path}")
 endmacro(REVERSE_PATH)
 
 macro(GET_COMMON_ROOT_PATH dir1 dir2 common_subpath)
+  get_filename_component(testpath "${dir1}" REALPATH)
   set(dir1_rev)
   set(dir2_rev)
-  REVERSE_PATH("${dir1}" dir1_rev)
-  REVERSE_PATH("${dir2}" dir2_rev)
-  set(component_same 1)
-  set(${common_subpath})
-  while(component_same)
-    get_filename_component(piece1 "${dir1_rev}" NAME)
-    get_filename_component(dir1_rev "${dir1_rev}" PATH)
-    get_filename_component(piece2 "${dir2_rev}" NAME)
-    get_filename_component(dir2_rev "${dir2_rev}" PATH)
-    if("${piece1}" STREQUAL "${piece2}")
-      set(${common_subpath} "${${common_subpath}}/${piece1}")
-    else("${piece1}" STREQUAL "${piece2}")
-      set(component_same 0)
-    endif("${piece1}" STREQUAL "${piece2}")
-  endwhile(component_same)
+  REVERSE_PATH("${dir1}" dir1_rev drive_name_1)
+  REVERSE_PATH("${dir2}" dir2_rev drive_name_2)
+  if("${drive_name_1}" STREQUAL "${drive_name_2}")
+    set(component_same 1)
+    set(${common_subpath})
+    while(component_same)
+      get_filename_component(piece1 "${dir1_rev}" NAME)
+      get_filename_component(dir1_rev "${dir1_rev}" PATH)
+      get_filename_component(piece2 "${dir2_rev}" NAME)
+      get_filename_component(dir2_rev "${dir2_rev}" PATH)
+      if("${piece1}" STREQUAL "${piece2}")
+	set(${common_subpath} "${${common_subpath}}/${piece1}")
+      else("${piece1}" STREQUAL "${piece2}")
+	set(component_same 0)
+      endif("${piece1}" STREQUAL "${piece2}")
+    endwhile(component_same)
+    if(drive_name_1)
+      set(${common_subpath} "${drive_name_1}${${common_subpath}}")
+      string(REPLACE "//" "/" ${common_subpath} "${${common_subpath}}")
+    endif(drive_name_1)
+  endif("${drive_name_1}" STREQUAL "${drive_name_2}")
 endmacro(GET_COMMON_ROOT_PATH)