Resolution:
TIBCO Spotfire Analyst and TIBCO Spotfire Server can communicate both over IPV4 and IPV6 for all supported versions. There are however a few differences between the versions with regards to how the the server address can be defined in Spotfire Analyst when using IPV6.

In 7.6 and 7.5, you can add the servers both using DNS names that resolves to IPV6 addresses as well as using the IPV6 address directly using the following syntax: http://[address%zoneID]:port/

It should also be possible to remove the zoneID and as follows: http://[address]:port/

In version 7.0 and prior versions, it will not allow you to enter an address as above even though IPV6 is supported. Instead you will have to add this using DNS names. For example:

http://myserver:8080

instead of:

http://[myiptoserver]:8080/

Defining server address using IPV6 in TIBCO Spotfire installed client