I only found a page that claims the following:
"Before you switch to UTF-8 under Linux, update your installation to a recent distribution with up-to-date UTF-8 support. This is particular the case if you use an installation older than SuSE 9.1 or Red Hat 8.0. Before these, UTF-8 support was not yet mature enough to be recommendable for daily use.
Red Hat Linux 8.0 (September 2002) was the first distribution to take the leap of switching to UTF-8 as the default encoding for most locales. The only exceptions were Chinese/Japanese/Korean locales, for which there were at the time still too many specialized tools available that did not yet support UTF-8. This first mass deployment of UTF-8 under Linux caused most remaining issues to be ironed out rather quickly during 2003. SuSE Linux then switched its default locales to UTF-8 as well, as of version 9.1 (May 2004). It was followed by Ubuntu Linux, the first Debian-derivative that switched to UTF-8 as the system-wide default encoding. With the migration of the three most popular Linux distributions, UTF-8 related bugs have now been fixed in practically all well-maintained Linux tools. Other distributions can be expected to follow soon. " (
UTF - 8 and Unicode FAQ for Unix/Linux)