Index: source/blender/src/filesel.c
===================================================================
--- source/blender/src/filesel.c	(revision 15149)
+++ source/blender/src/filesel.c	(working copy)
@@ -2137,8 +2137,12 @@
 
 		case IKEY:
 			if(sfile->type==FILE_MAIN) break;
+#ifdef WIN32					
+			sprintf(str, "%%IMAGEEDITOR%% %s%s", sfile->dir, sfile->file);
+#else
+			sprintf(str, "$IMAGEEDITOR %s%s", sfile->dir, sfile->file);
+#endif
 			
-			sprintf(str, "$IMAGEEDITOR %s%s", sfile->dir, sfile->file);
 			system(str);
 			break;