Either wp-admin/includes or wp-includes as class-xxx.php.
The choice between the two is basically whether or not the file is
useful outside the admin context.
If you can envisage it being used by a plugin which provides frontend
functionality then wp-includes. Otherwise wp-admin/includes it is.
westi
- --
Peter Westwood
http://blog.ftwr.co.uk | http://westi.wordpress.com
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