Hi,

there is a module for that made by nan tic, module name is nan_product_pack, hoping it will works for your version, I had some bugs with it in 6.0, but I think author Albert Cervera had corrected its. You can define a pack composed by other packs, define price by its componants or just with a fixed price. In sale order lines your have parent product and sublines beginning with ">". Warning with drag and drop in line, there is no function which reorder lines after a move.

You can find module on appps :

http://v6apps.openerp.com/addon/1542

or extra addons :

http://bazaar.launchpad.net/~openerp-commiter/openobject-addons/stable_5.0-extra-addons/files

http://bazaar.launchpad.net/~openerp-commiter/openobject-addons/extra-6.0/files

http://bazaar.launchpad.net/~openerp-commiter/openobject-addons/trunk-extra-addons/files

Bye