Problems with IPv6 web hosting in Virtualmin.

Before I go submitting bug reports, I want to make sure that I'm doing things right.

I'm trying to set up our web server as a dual-stacked system now that our ISP is provisioning native IPv6. My attempts to set up our current domains with new addresses haven't been too successful, and I can see why by looking at the Apache configuration.

My configuration: Debian 5.0 (Lenny) Virtualmin 3.80.gpl GPL Webmin 1.520

Procedure 1:

1. Configure v6 IP ranges in System Settings -> Server Templates -> Default Settings -> Virtual IP Addresses.
2. Configure default IPv6 netmask size in System Settings -> Virtualmin Configuration -> Network Settings
3. I try to set up an existing domain for IPv6 in Edit Virtual Server -> IP Addresses and Interfaces -> Create Now with Allocated IP

Trying to save these settings in step 3 results in the error message "Failed to modify server : Missing or invalid IPv6 address". I've also tried the following procedure:

Procedure 2 (manual IP assignment, would rather use procedure 1):

1. Turn off v6 IP ranges in step 1 above (or use the default configuration).
2. Set up a v6 IP address manually on an existing domain in: Edit Virtual Servers -> IP Addresses and Interfaces -> Using Address:

This method usually breaks Apache by not setting a NameVirtualHost entry for the IP address (in my case, in /etc/apache2/sites-enabled/000-default). Restarting apache results in an error saying that there is no such VirtualHost. The default Virtualmin configuration typically also doesn't set the netmask right in the network configuration, but it looks like setting the default IPv6 netmask size in step 2 of procedure 1 fixes this problem.

Is my procedure correct, or am I missing something?