diff --git a/ChangeLog b/ChangeLog
index a0aecd64a9a..3c9576e7544 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -16,6 +16,7 @@ NEW: Module DebugBar is available as a stable module.
 WARNING:
 
 Following changes may create regressions for some external modules, but were necessary to make Dolibarr better:
+* The PHP extension php-intl is not mandatory but should be installed to have new features working correctly.
 * Method GetUrlTrackingStatus were renamed into getUrlTrackingStatus for consistency with naming rules.
 * API getListOfCivility has been renamed into getListOfCivilities for consistency with naming rules.
 * Deprecated function img_phone as been removed. You can use img_picto(..., 'call|call_out') instead.; 
diff --git a/htdocs/install/check.php b/htdocs/install/check.php
index 3477ad1d041..e73b4eca70b 100644
--- a/htdocs/install/check.php
+++ b/htdocs/install/check.php
@@ -161,6 +161,19 @@ else
 }
 
 
+// Check if UTF8 supported
+if (! function_exists("locale_get_primary_language"))
+{
+    $langs->load("errors");
+    print '<img src="../theme/eldy/img/warning.png" alt="Error"> '.$langs->trans("ErrorPHPDoesNotSupportIntl")."<br>\n";
+    // $checksok=0;		// If image ko, just warning. So check must still be 1 (otherwise no way to install)
+}
+else
+{
+    print '<img src="../theme/eldy/img/tick.png" alt="Ok"> '.$langs->trans("PHPSupportIntl")."<br>\n";
+}
+
+
 
 // Check memory
 $memrequiredorig='64M';
diff --git a/htdocs/langs/en_US/install.lang b/htdocs/langs/en_US/install.lang
index e89257002a4..2fe7dc8c038 100644
--- a/htdocs/langs/en_US/install.lang
+++ b/htdocs/langs/en_US/install.lang
@@ -14,6 +14,7 @@ PHPSupportPOSTGETKo=It's possible your PHP setup does not support variables POST
 PHPSupportGD=This PHP supports GD graphical functions.
 PHPSupportCurl=This PHP supports Curl.
 PHPSupportUTF8=This PHP supports UTF8 functions.
+PHPSupportIntl=This PHP supports Intl functions.
 PHPMemoryOK=Your PHP max session memory is set to <b>%s</b>. This should be enough.
 PHPMemoryTooLow=Your PHP max session memory is set to <b>%s</b> bytes. This is too low. Change your <b>php.ini</b> to set <b>memory_limit</b> parameter to at least <b>%s</b> bytes.
 Recheck=Click here for a more detailed test
@@ -21,6 +22,7 @@ ErrorPHPDoesNotSupportSessions=Your PHP installation does not support sessions.
 ErrorPHPDoesNotSupportGD=Your PHP installation does not support GD graphical functions. No graphs will be available.
 ErrorPHPDoesNotSupportCurl=Your PHP installation does not support Curl.
 ErrorPHPDoesNotSupportUTF8=Your PHP installation does not support UTF8 functions. Dolibarr cannot work correctly. Resolve this before installing Dolibarr.
+ErrorPHPDoesNotSupportIntl=Your PHP installation does not support Intl functions.
 ErrorDirDoesNotExists=Directory %s does not exist.
 ErrorGoBackAndCorrectParameters=Go back and check/correct the parameters.
 ErrorWrongValueForParameter=You may have typed a wrong value for parameter '%s'.