diff --git a/setup/inc/class.setup_translation.inc.php b/setup/inc/class.setup_translation.inc.php
index 14c1428ac2..0a193ee94e 100644
--- a/setup/inc/class.setup_translation.inc.php
+++ b/setup/inc/class.setup_translation.inc.php
@@ -16,6 +16,9 @@
 		define('MAX_MESSAGE_ID_LENGTH',128);
 	}
 
+	// Define prefix for langfiles (historically 'phpgw_')
+	define('EGW_LANGFILE_PREFIX', 'egw_');
+
 	class setup_translation
 	{
 		var $langarray = array();
@@ -40,10 +43,10 @@
 				$lang = $ConfigLang;
 			}
 			
-			$fn = '.' . SEP . 'lang' . SEP . 'phpgw_' . $lang . '.lang';
+			$fn = '.' . SEP . 'lang' . SEP . EGW_LANGFILE_PREFIX . $lang . '.lang';
 			if (!file_exists($fn))
 			{
-				$fn = '.' . SEP . 'lang' . SEP . 'phpgw_en.lang';
+				$fn = '.' . SEP . 'lang' . SEP . EGW_LANGFILE_PREFIX .'en.lang';
 			}
 			if (file_exists($fn))
 			{
@@ -151,7 +154,7 @@
 				while(($line = fgets($f)) !== false)
 				{
 					list($lang,$language) = explode("\t",trim($line));
-					if ($lang && ($lf = @fopen("../phpgwapi/setup/phpgw_$lang.lang",'r')))
+					if ($lang && ($lf = @fopen("../phpgwapi/setup/" . EGW_LANGFILE_PREFIX . "$lang.lang",'r')))
 					{
 						while(($line = fgets($lf)) !== false)
 						{
diff --git a/setup/lang/phpgw_bg.lang b/setup/lang/egw_bg.lang
similarity index 100%
rename from setup/lang/phpgw_bg.lang
rename to setup/lang/egw_bg.lang
diff --git a/setup/lang/phpgw_ca.lang b/setup/lang/egw_ca.lang
similarity index 100%
rename from setup/lang/phpgw_ca.lang
rename to setup/lang/egw_ca.lang
diff --git a/setup/lang/phpgw_cs.lang b/setup/lang/egw_cs.lang
similarity index 100%
rename from setup/lang/phpgw_cs.lang
rename to setup/lang/egw_cs.lang
diff --git a/setup/lang/phpgw_de.lang b/setup/lang/egw_de.lang
similarity index 100%
rename from setup/lang/phpgw_de.lang
rename to setup/lang/egw_de.lang
diff --git a/setup/lang/phpgw_en.lang b/setup/lang/egw_en.lang
similarity index 100%
rename from setup/lang/phpgw_en.lang
rename to setup/lang/egw_en.lang
diff --git a/setup/lang/phpgw_es-es.lang b/setup/lang/egw_es-es.lang
similarity index 100%
rename from setup/lang/phpgw_es-es.lang
rename to setup/lang/egw_es-es.lang
diff --git a/setup/lang/phpgw_fi.lang b/setup/lang/egw_fi.lang
similarity index 100%
rename from setup/lang/phpgw_fi.lang
rename to setup/lang/egw_fi.lang
diff --git a/setup/lang/phpgw_fr.lang b/setup/lang/egw_fr.lang
similarity index 100%
rename from setup/lang/phpgw_fr.lang
rename to setup/lang/egw_fr.lang
diff --git a/setup/lang/phpgw_hr.lang b/setup/lang/egw_hr.lang
similarity index 100%
rename from setup/lang/phpgw_hr.lang
rename to setup/lang/egw_hr.lang
diff --git a/setup/lang/phpgw_hu.lang b/setup/lang/egw_hu.lang
similarity index 100%
rename from setup/lang/phpgw_hu.lang
rename to setup/lang/egw_hu.lang
diff --git a/setup/lang/phpgw_it.lang b/setup/lang/egw_it.lang
similarity index 100%
rename from setup/lang/phpgw_it.lang
rename to setup/lang/egw_it.lang
diff --git a/setup/lang/phpgw_iw.lang b/setup/lang/egw_iw.lang
similarity index 100%
rename from setup/lang/phpgw_iw.lang
rename to setup/lang/egw_iw.lang
diff --git a/setup/lang/phpgw_ja.lang b/setup/lang/egw_ja.lang
similarity index 100%
rename from setup/lang/phpgw_ja.lang
rename to setup/lang/egw_ja.lang
diff --git a/setup/lang/phpgw_ko.lang b/setup/lang/egw_ko.lang
similarity index 100%
rename from setup/lang/phpgw_ko.lang
rename to setup/lang/egw_ko.lang
diff --git a/setup/lang/phpgw_lt.lang b/setup/lang/egw_lt.lang
similarity index 100%
rename from setup/lang/phpgw_lt.lang
rename to setup/lang/egw_lt.lang
diff --git a/setup/lang/phpgw_lv.lang b/setup/lang/egw_lv.lang
similarity index 100%
rename from setup/lang/phpgw_lv.lang
rename to setup/lang/egw_lv.lang
diff --git a/setup/lang/phpgw_nl.lang b/setup/lang/egw_nl.lang
similarity index 100%
rename from setup/lang/phpgw_nl.lang
rename to setup/lang/egw_nl.lang
diff --git a/setup/lang/phpgw_no.lang b/setup/lang/egw_no.lang
similarity index 100%
rename from setup/lang/phpgw_no.lang
rename to setup/lang/egw_no.lang
diff --git a/setup/lang/phpgw_pl.lang b/setup/lang/egw_pl.lang
similarity index 100%
rename from setup/lang/phpgw_pl.lang
rename to setup/lang/egw_pl.lang
diff --git a/setup/lang/phpgw_pt-br.lang b/setup/lang/egw_pt-br.lang
similarity index 100%
rename from setup/lang/phpgw_pt-br.lang
rename to setup/lang/egw_pt-br.lang
diff --git a/setup/lang/phpgw_pt.lang b/setup/lang/egw_pt.lang
similarity index 100%
rename from setup/lang/phpgw_pt.lang
rename to setup/lang/egw_pt.lang
diff --git a/setup/lang/phpgw_ru.lang b/setup/lang/egw_ru.lang
similarity index 100%
rename from setup/lang/phpgw_ru.lang
rename to setup/lang/egw_ru.lang
diff --git a/setup/lang/phpgw_sk.lang b/setup/lang/egw_sk.lang
similarity index 100%
rename from setup/lang/phpgw_sk.lang
rename to setup/lang/egw_sk.lang
diff --git a/setup/lang/phpgw_sl.lang b/setup/lang/egw_sl.lang
similarity index 100%
rename from setup/lang/phpgw_sl.lang
rename to setup/lang/egw_sl.lang
diff --git a/setup/lang/phpgw_sv.lang b/setup/lang/egw_sv.lang
similarity index 100%
rename from setup/lang/phpgw_sv.lang
rename to setup/lang/egw_sv.lang
diff --git a/setup/lang/phpgw_zh-tw.lang b/setup/lang/egw_zh-tw.lang
similarity index 100%
rename from setup/lang/phpgw_zh-tw.lang
rename to setup/lang/egw_zh-tw.lang
diff --git a/setup/lang/phpgw_zh.lang b/setup/lang/egw_zh.lang
similarity index 100%
rename from setup/lang/phpgw_zh.lang
rename to setup/lang/egw_zh.lang