[nznog] IP Management software at ISP/Carrier scale

So, I'm looking at this ipv6 assignment from the good folks at APNIC, and I'm also looking at my current, aging, not-very-scalable IP Management system, and I'm not liking where I see this going. I'm interested to hear NZNOGs suggestions about decent, scalable, software (preferably off-the-shelf) to handle v4 and v6 IP management. Open source stuff welcome, though commercial, supported software is also fine. I'm just wondering what you cool kids are using to manage their address space these days. Feedback, thoughts and opinions welcome. - JSR