Although the active members of the Hamilton Group of Unix dissidents opposed to AT&T Co’s relationship with Sun Microsystems Inc – on the grounds that future releases of Unix are likely to be available on the Sparc ahead of any other processor, giving Sun an unfair advantage – seem to have shrunk to DEC, Hewlett-Packard Co and Apollo Computer Inc, word is that that trio – plus, some rather surprisingly suggest, perhaps IBM as well – plan to come together to make a formal challenge this week to AT&T’s whole approach to the licensing of Unix.