In solaris it is possible to vlan tag your network interfaces. The main file you will want to work with is the /etc/hostname.xxxx file, where xxxx is your interface. Below is an example of a sample solaris interface:
root@solaris:~# ls -lah /etc/hostname.* -rw-r--r-- 1 root root 13 2011-07-20 05:21 /etc/hostname.e1000g0
This is just the default e1000g0 interface. Taking the interface, we will implement a vlan tag.
Simply rename the file from /etc/hostname.e1000g0 to /etc/hostname.e1000g
It is essentially the driver, then vlan id, times 1000, and the last digit being the interface number. In this case it would look something like, supposing the vlan id was 9838:
Then follow up by plumbing the interfaces.
ifconfig -a plumb
Always implement these types of changes in a development environment first before deploying in production to avoid errors.