--- a/git/GitRepository.st	Mon Sep 10 10:32:46 2012 +0000
+++ b/git/GitRepository.st	Mon Sep 10 13:37:31 2012 +0000
@@ -59,12 +59,13 @@
     ].
     ref := ByteArray new: ExternalBytes sizeofPointer.
     err := GitPrimitives prim_git_object_lookup: ref repo: self id: oid type: typeId.
-    err ~~ 0 ifTrue:[
-        self error:'gitlib2 error'
-    ].
+    GitError raiseIfError: err.
+
     typeId == OBJ_ANY ifTrue:[
         obj := ExternalAddress new setAddressFromBytes:ref.
         type := GitPrimitives prim_git_object_type: obj.
+    ] ifFalse:[
+        type := typeId.
     ].
     ^GitObject type: type addressBytes: ref.