diff --git a/update_current.py b/update_current.py
index 0f86319..2820192 100755
--- a/update_current.py
+++ b/update_current.py
@@ -265,7 +265,7 @@
         # Unclear if this is actually necessary.
         extract_to(zipFile, paths, 'framework.aidl', system_path)
 
-    artifact_path = fetch_artifact(target, build_id, 'core.current.stubs.jar')
+    artifact_path = fetch_artifact(target, build_id.fs_id, 'core.current.stubs.jar')
     if not artifact_path:
         return False