Upgrading to a different software group 

You cannot upgrade your system to a software group that is not installed on the system. For example, if you previously installed the End User Solaris Software Group on your system, you cannot use the upgrade option to upgrade to the Developer Solaris Software Group. However, during the upgrade you can add software to the system that is not part of the currently installed software group. 

Starting with the Solaris 10 1/06 release: Upgrading when non-global zones are installed

When you are upgrading the Solaris OS, you can upgrade a system that has non-global zones installed. The Solaris interactive installation program and custom JumpStart programs enable an upgrade. For limitations when upgrading, see Upgrading When Non-Global Zones Are Installed.