diff --git a/core/src/net/sf/openrocket/gui/util/SwingPreferences.java b/core/src/net/sf/openrocket/gui/util/SwingPreferences.java
index 233bd9bfc..764070880 100644
--- a/core/src/net/sf/openrocket/gui/util/SwingPreferences.java
+++ b/core/src/net/sf/openrocket/gui/util/SwingPreferences.java
@@ -38,7 +38,7 @@ public class SwingPreferences extends net.sf.openrocket.startup.Preferences {
 	private static final List<Locale> SUPPORTED_LOCALES;
 	static {
 		List<Locale> list = new ArrayList<Locale>();
-		for (String lang : new String[] { "en", "de", "es", "fr", "it", "ru" }) {
+		for (String lang : new String[] { "en", "de", "es", "fr", "it", "ru","cs" }) {
 			list.add(new Locale(lang));
 		}
 		SUPPORTED_LOCALES = Collections.unmodifiableList(list);