diff --git a/src/Generator/MoGenerator.php b/src/Generator/MoGenerator.php
index 5edb68e..e815101 100644
--- a/src/Generator/MoGenerator.php
+++ b/src/Generator/MoGenerator.php
@@ -45,7 +45,7 @@ public function generateString(Translations $translations): string
             $messages[$originalString] = $translation;
         }
 
-        ksort($messages);
+        ksort($messages, SORT_STRING);
         $numEntries = count($messages);
         $originalsTable = '';
         $translationsTable = '';
diff --git a/tests/MoGeneratorTest.php b/tests/MoGeneratorTest.php
index 06b3f5d..a3e246d 100644
--- a/tests/MoGeneratorTest.php
+++ b/tests/MoGeneratorTest.php
@@ -36,6 +36,10 @@ public function testMoGenerator()
         $translation->translate('Comentario deshabilitado');
         $translations->add($translation);
 
+        $translation = Translation::create(null, '15');
+        $translation->translate('15');
+        $translations->add($translation);
+
         $translation = Translation::create(null, '123456');
         $translation->translate('12345');
         $translations->add($translation);
@@ -47,7 +51,7 @@ public function testMoGenerator()
 
         $result = $loader->loadString($mo);
 
-        $this->assertCount(3, $result);
+        $this->assertCount(4, $result);
         $this->assertCount(5, $result->getHeaders());
     }
 }
diff --git a/tests/assets/mo-generator-result.mo b/tests/assets/mo-generator-result.mo
index cc7feb7..b717abe 100644
Binary files a/tests/assets/mo-generator-result.mo and b/tests/assets/mo-generator-result.mo differ