[ESS] Snw files are not weaved by C-c C-c from AucTeX-mode

[jens.scheidtmann at bayerbbs.com]

Dear list,

Today I installed ESS 5.3.1 on GNU Emacs 21.3.50.1 on W2K.
Before that I already had installed AUCTeX 11.13 with RefTeX, which was/is
working smoothly.

I have downloaded example-1.Snw from the Sweave download area here:
http://www.ci.tuwien.ac.at/~leisch/Sweave/

On loading the .Snw file, the mode line shows "LaTeX Ref Fill Noweb NWFL" on
documentation chunks and "ESS[S] [R] noweb" on code chunks.
C-h m (Describe Buffer Modes) shows that "LaTeX" stems from AucTeX, so it seems
the correct modes are started.

By C-c C-j I am able to execute single lines in R 2.3.1. Or even chunks by using
the respective menu entries.

C-c C-c LaTeX on a documentation chunk starts LaTeX (MikTeX), but the following
error message occurs:

---snip---
Running `LaTeX' on `example-1.Snw' with ``latex --src-specials
\nonstopmode\input{example-1.Snw.tex}''
This is e-TeX, Version 3.141592-2.1 (MiKTeX 2.4)
entering extended mode
LaTeX2e <2001/06/01>
Babel <v3.7m> and hyphenation patterns for english, french, german, ngerman, du
mylang, nohyphenation, loaded.


! LaTeX Error: File `example-1.Snw.tex' not found.
...
----

I can weave from the R Buffer using:
> Sweave("example-1.Snw")

Processing the resulting LaTeX file through Emacs/AucTeX again works.

Can somebody familiar with ESS / noweb please comment on this?
Did I miss some obvious configuration items?
If, yes, which ones?
Do you need more information?

Thanks in advance,

Jens