--- a/AbstractOperatingSystem.st	Sun May 20 10:13:17 2018 +0200
+++ b/AbstractOperatingSystem.st	Sun May 20 10:35:25 2018 +0200
@@ -18,7 +18,7 @@
 Object subclass:#AbstractOperatingSystem
 	instanceVariableNames:''
 	classVariableNames:'ConcreteClass ErrorSignal LastErrorNumber LocaleInfo OSSignals
-		PipeFailed Resources VoiceMapping'
+		PipeFailed Resources VoiceMapping DefaultVoice'
 	poolDictionaries:''
 	category:'System-Support'
 !
@@ -1140,6 +1140,7 @@
     "Created: / 12.11.1998 / 14:39:20 / cg"
 ! !
 
+
 !AbstractOperatingSystem class methodsFor:'executing OS commands-public'!
 
 executeCommand:aCommandString
@@ -6620,9 +6621,13 @@
 
     |mapping voiceUsed|
 
-    mapping := self voiceMapping detect:[:v | v key = voiceName] ifNone:[(voiceName -> voiceName)].
-    voiceUsed := mapping value.
-
+    (voiceName isNil or:[voiceName = 'default']) ifTrue:[
+        voiceUsed := DefaultVoice
+    ].  
+    voiceUsed isNil ifTrue:[
+        mapping := self voiceMapping detect:[:v | v key = voiceName] ifNone:[(voiceName -> voiceName)].
+        voiceUsed := mapping value.
+    ].
     self voiceCommandSpec triplesDo:[:cmd :cmdLineForDefaultVoice :cmdLineForVoice |
         |cmdLine|