Asset deactivation and deletion of Equipment!!!!!

Hi Gurus,

We are facing a problem while deactivating the asset for an equipment. Both Equipment and assets are created with the same number in the system. Can any one tell me if I can link an equipment with an assets, when both are created with the same number, in the system? Both Equipment and asset numbers are mentioned in each others master record, is there a setting in the system which can, while retiring the asset, check if the euipment is off use or not before actually retiring the asset?

thanks in advance

Anoop