ZFS is the main file system used in Oracle Solaris 11. ZFS uses the locale's character set to store file and directory names like other file systems. For the UTF-8 character set, the normalization property sets the type of normalization algorithm used by the file system for comparing names to avoid having more than one entity with the same file name in a single directory.
If the utf8only property is enabled, the file system will reject file names that include characters not present in the UTF-8 character set.
See the zfs(1) man page for more information.