I'd say just dont touch the constants, apart from adding a comment:
```
define('ATTACHMENT_CATEGORY_NONE', 0);
define('ATTACHMENT_CATEGORY_IMAGE', 1); // Inline Images
define('ATTACHMENT_CATEGORY_WM', 2); // Windows Media Files - @deprecated 3.1
define('ATTACHMENT_CATEGORY_RM', 3); // Real Media Files - @deprecated 3.1
define('ATTACHMENT_CATEGORY_THUMB', 4); // Not used within the database, only while displaying posts
define('ATTACHMENT_CATEGORY_FLASH', 5); // Flash/SWF files
define('ATTACHMENT_CATEGORY_QUICKTIME', 6); // Quicktime/Mov files - @deprecated 3.1
```