Bug? how to obtain diff between current file content and some revision?

[Alexander Belchenko]

Is this exist simple way to obtain diff between current file content 
(not last revision) and some past revision?

When I do `bzr diff FILENAME` I get diff between last revision and 
current state.

When I do `bzr diff -rN.. FILENAME` I get diff between specified 
revision and NULL, i.e. with state when this file was not exist. Is this 
  intended behaviour?

Here example:

E:\work\Python\bzr\test\diff>bzr init
E:\work\Python\bzr\test\diff>bzr add
added spam.txt

E:\work\Python\bzr\test\diff>bzr ci -m "test"

<hack hack>

E:\work\Python\bzr\test\diff>bzr diff
=== modified file 'spam.txt'
--- spam.txt
+++ spam.txt
@@ -1,2 +1,3 @@
+-----
  12345
  67890

E:\work\Python\bzr\test\diff>bzr diff -r1..
=== removed file 'spam.txt'
--- spam.txt
+++ /dev/null
@@ -1,2 +0,0 @@
-12345
-67890


-------------------------------------------------

Alexander