I got this from a website:
SUDO for solaris
Installing Packages from website
Download from
http://www.sunfreeware.com/ftp/pub/freeware/companioncd/intel/nevada/Unzip compressed package
bunzip2 SFWsudo.pkg.bz2
Install package
pkgadd -d SFWsudo.pkg
Using sudo package
ln -s /opt/sfw/sbin/visudo /usr/sbin/visudo
ln -s /opt/sfw/bin/sudo /usr/bin/sudo
ln -s /opt/sfw/etc/sudoers /etc/sudoers
Add wheel group and users to wheel group
cat /etc/group | grep wheel
wheel::11:root,anwar
Uncomment the line in /etc/sudoers
cat /etc/sudoers | grep wheel | grep -v \#
%wheel ALL=(ALL) NOPASSWD: SETENV: ALL
sudo needs to be setuid root in order to work
chmod 4111 /opt/sfw/bin/sudo
then login as your user, then type sudo su -