Some people are annoyed by the Solregis pop-up, especially if you
do not want all users to register.
Create /etc/default/solregis and put the following in it:
This prevents the solregis program from starting.
The manual lists a method to disable it on a per-user basis.
Registering with solregis gives access to SolarisSolve; this
enables you to fetch the Maintenance Updates.
You can also remove the SUNWsregu package or don't install it
in the first place.