diff --git a/src/main/php/PDepend/Source/AST/AbstractASTArtifact.php b/src/main/php/PDepend/Source/AST/AbstractASTArtifact.php
index 43bd7a1c3b..0096ddf109 100644
--- a/src/main/php/PDepend/Source/AST/AbstractASTArtifact.php
+++ b/src/main/php/PDepend/Source/AST/AbstractASTArtifact.php
@@ -145,7 +145,7 @@ public function setName($name)
     public function getId()
     {
         if ($this->id === null) {
-            $this->id = md5(microtime());
+            $this->id = md5(uniqid('', TRUE));
         }
         return $this->id;
     }