My guess would be that you are probably going to be as out of luck with that older firewall as I was with my older model Cisco RV082.
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www.juniper.net/us/en/pr ··· e/ns5gt/Overview
Last order date: December 31, 2008
The NetScreen-5GT appliance is an enterprise-class, network security solution that integrates best-in-class UTM security features, including IPS, antivirus (includes anti-spyware, anti-adware, anti-phishing), anti-spam, and Web filtering.
The NetScreen-5GT is end of sale, and in its place, we recommend the SSG5 and SSG20, high-performance security appliances that offer LAN/WAN connectivity for small branch offices and standalone business deployments.
FWIW, the NS5GT user manual makes no mention whatsoever of IPv6 (just like my older model Cisco RV082 router)
