Notes about setting up dtrace user on a Solaris 10 system: by default, it appears that normal users don't have enough privileges to access dtrace. These privileges are:
and these are described in the privileges(5) man page.
So how do we add these privileges to a user account? According to http://forum.sun.com/thread.jspa?threadID=22787&messageID=73761, it's a matter of editing /etc/user_attr with a set of default privileges.