diff --git a/main/inc/lib/internationalization.lib.php b/main/inc/lib/internationalization.lib.php
index 2a46e8aa2d..1367154a76 100755
--- a/main/inc/lib/internationalization.lib.php
+++ b/main/inc/lib/internationalization.lib.php
@@ -66,7 +66,7 @@ function api_initialize_internationalization() {
 		@ini_set('mbstring.http_output', 'pass');
 		@ini_set('mbstring.language', 'neutral');
 	}
-	api_set_internationalization_default_encoding('ISO-8859-15');
+	api_set_internationalization_default_encoding('UTF-8');
 }
 
 /**
diff --git a/main/inc/lib/internationalization_internal.lib.php b/main/inc/lib/internationalization_internal.lib.php
index d0f3a1ecef..a08eb8ef1d 100755
--- a/main/inc/lib/internationalization_internal.lib.php
+++ b/main/inc/lib/internationalization_internal.lib.php
@@ -966,7 +966,7 @@ function _api_mb_internal_encoding($encoding = null) {
 			if (MBSTRING_INSTALLED) {
 				$mb_internal_encoding = @mb_internal_encoding();
 			} else {
-				$mb_internal_encoding = 'ISO-8859-15';
+				$mb_internal_encoding = 'UTF-8';
 			}
 		}
 		return $mb_internal_encoding;
@@ -992,7 +992,7 @@ function _api_mb_regex_encoding($encoding = null) {
 			if (MBSTRING_INSTALLED) {
 				$mb_regex_encoding = @mb_regex_encoding();
 			} else {
-				$mb_regex_encoding = 'ISO-8859-15';
+				$mb_regex_encoding = 'UTF-8';
 			}
 		}
 		return $mb_regex_encoding;