Which company made the first IPv6-compatible product ?

Yesterady, I took part in an online quiz on IPv6 of 10 questions and I could answer 9 questions correct.  There was a question asking which company first made the commercial IPv6-compatible product.  The choice were : Cisco, Digital Equipment Corporation, IBM, and Novell.  I picked Cisco as IPv6 backbone must bre ready before any IPv6 applications can be realized.  The answer was wrong.  It was IBM that offered IBM AIX 4.3 in 1997 which was the first product to support IPv6 in the market.