If you need to add support to additional locales on an already installed Solaris system, then you have to do the following:

SOLARIS 11

1. Determine the locale name you want to install. You can see the available locales here

2. Install legacy locales support (Optional)

By default, Solaris 11 supports UTF-8 locales installation, if you need to add other type of locales (like ISO8859-1), you should do the following:

# pkg install pkg:/system/locale/extra

3. Install the locale

// To install all the spanish locales
# pkg change-facet facet.locale.es=True

// To install only the french locale corresponding to Canada
# pkg change-facet facet.locale.fr_CA=True

SOLARIS 10

1. List all locales available:

# localeadm -l

Look for the short name of the locale in the output generated by the previous command (the short name is between parenthesis, for example, to look for South America):

Checking for South America region (sam)
(c_solaris packages)
|..|

No packages found.

2. Install using localeadm:

# localeadm -a sam -d /cdrom/cdrom0/s0

-d <package_location> specifies the location of the locale packages, in this example is in the Solaris Installation DVD