tramp and make-auto-save-file-name

[Jean Magnan de Bornier]

Hi all,
Emacs here is:
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This is GNU Emacs 22.0.50.1 (i686-pc-linux-gnu, GTK+ Version 2.8.19)
 of 2006-10-14 on boldair
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When I want to use tramp I always get messages like this:

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tramp: Encoding remote file /ssh:borixe:/home/jean/.emacs...
tramp: Decoding remote file /ssh:borixe:/home/jean/.emacs...
Mark set
tramp: Decoding remote file /ssh:borixe:/home/jean/.emacs with function
base64-decode-region...
Wrote /tmp/tramp.9137Ult
tramp: Decoding remote file /ssh:borixe:/home/jean/.emacs...done
tramp: Inserting local temp file `/tmp/tramp.9137Ult'...done
tramp-file-name-for-operation: unknown file I/O primitive:
make-auto-save-file-name
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Then nothing happens but if I retry to open the remote file then it works
like a charm; if I try another file the same behavior happens again
(needing two tries for tramp to succeed). I saw some posts about that on
google but was not able to understand them.
Any help here?
tia,
-- 
  Jean