Index: expand.c
===================================================================
RCS file: /cvsroot/boost/boost/tools/build/jam_src/expand.c,v
retrieving revision 1.10
diff -b -d -u -b -u -r1.10 expand.c
--- expand.c	12 Feb 2005 02:30:16 -0000	1.10
+++ expand.c	3 Nov 2005 15:43:01 -0000
@@ -634,14 +634,43 @@
  * var_edit_shift() - do upshift/downshift mods
  */
 
+static char cygdrive[] = "/cygdrive/";
+
 static void
 var_edit_shift( 
 	string	*out,
 	VAR_EDITS *edits )
 {
 	/* Handle upshifting, downshifting and slash translation now */
-
     char *p;
+
+    if ( edits->to_windows )
+    {
+# ifdef OS_CYGWIN
+        char result[MAX_PATH + 1];
+        cygwin_conv_to_win32_path(out->value, result);
+        assert(strlen(result) <= MAX_PATH);
+        string_free( out );
+        string_copy( out, result );
+# else
+        
+#  define DRIVELETTER (sizeof(cygdrive) - 1)
+        if (!strncmp(out->value, cygdrive, sizeof(cygdrive) - 1)
+            && out->value[DRIVELETTER]
+            && out->value[DRIVELETTER + 1] == '/'
+        )
+        {
+            out->value[0] = out->value[DRIVELETTER];
+            out->value[1] = ':';
+            memmove(
+                out->value + 2
+              , out->value + DRIVELETTER + 1, (out->size + 1) - (DRIVELETTER + 1) 
+            );
+            out->size -= DRIVELETTER - 1; /* leaving room for the colon */
+        }
+    }
+# endif
+    
     for ( p = out->value; *p; ++p)
     {
         if (edits->upshift)
@@ -657,17 +686,14 @@
             if ( *p == '\\')
                 *p = '/';
         }
-# ifdef OS_CYGWIN
         if ( edits->to_windows )
         {
-            char result[MAX_PATH + 1];
-            cygwin_conv_to_win32_path(out->value, result);
-            assert(strlen(result) <= MAX_PATH);
-            string_free( out );
-            string_copy( out, result );
-        }
+# ifndef OS_CYGWIN
+            if (*p == '/')
+                *p = '\\';
 # endif
     }
+    }
     out->size = p - out->value;
 }
 
@@ -702,11 +728,7 @@
     l = var_expand( 0, path, path + sizeof(path) - 1, lol, 0 );
     assert(l != 0);
     assert(list_next(l) == 0);
-# ifdef OS_CYGWIN
     assert( !strcmp( l->string, "c:\\foo\\bar" ) );
-# else 
-    assert( !strcmp( l->string, "/cygdrive/c/foo/bar" ) );
-# endif   
     list_free(l);
 
     list_free(expected);