diff --git a/htdocs/install/check.php b/htdocs/install/check.php
index 1e248071135..a8b38fe4620 100644
--- a/htdocs/install/check.php
+++ b/htdocs/install/check.php
@@ -147,6 +147,16 @@ else
     print '<img src="../theme/eldy/img/tick.png" alt="Ok"> '.$langs->trans("PHPSupportCurl")."<br>\n";
 }
 
+// Check if PHP calendar extension is available
+if (! function_exists("easter_date"))
+{
+    print '<img src="../theme/eldy/img/warning.png" alt="Error"> '.$langs->trans("ErrorPHPDoesNotSupportCalendar")."<br>\n";
+}
+else
+{
+    print '<img src="../theme/eldy/img/tick.png" alt="Ok"> '.$langs->trans("PHPSupportCalendar")."<br>\n";
+}
+
 
 // Check if UTF8 supported
 if (! function_exists("utf8_encode"))
diff --git a/htdocs/langs/en_US/install.lang b/htdocs/langs/en_US/install.lang
index 2fe7dc8c038..3ef3532a08e 100644
--- a/htdocs/langs/en_US/install.lang
+++ b/htdocs/langs/en_US/install.lang
@@ -13,6 +13,7 @@ PHPSupportPOSTGETOk=This PHP supports variables POST and GET.
 PHPSupportPOSTGETKo=It's possible your PHP setup does not support variables POST and/or GET. Check the parameter <b>variables_order</b> in php.ini.
 PHPSupportGD=This PHP supports GD graphical functions.
 PHPSupportCurl=This PHP supports Curl.
+PHPSupportCalendar=This PHP supports calendars extensions.
 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.
@@ -21,6 +22,7 @@ Recheck=Click here for a more detailed test
 ErrorPHPDoesNotSupportSessions=Your PHP installation does not support sessions. This feature is required to allow Dolibarr to work. Check your PHP setup and permissions of the sessions directory.
 ErrorPHPDoesNotSupportGD=Your PHP installation does not support GD graphical functions. No graphs will be available.
 ErrorPHPDoesNotSupportCurl=Your PHP installation does not support Curl.
+ErrorPHPDoesNotSupportCalendar=Your PHP installation does not support php calendar extensions.
 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.