compatabile products

Hi,

Check Product compatabality in sales order,

i've created sales order with 4 differeent materails

10 Computer qty 1
20 pen qty 10
30 CD-ROM qty 4
40 shirt qty 2

50 CD qty 5

pen, harddisk, shirt are all flat products which are added in sales order separately/manually independent of computer.

1. is there any way to configure system to check whether materials pen/harddisk/shirt are not compatible with computer.

2. across item level check: system shopld check is CD compatible with CD-ROM material.

Requirement is system shoudn't allow customer to buy Pen, shirt since its not compatible with computer & CD-ROM.

can you pls. let me know how we can achieve this, other than using VC/material listing/exclusion.