Hi Eric,

I don't think they work yet.  See Eric Schulte's message to the  
mailing list on Oct. 27:

Re: [Orgmode] org babel and alternative output file when using +call

All the best,
Tom

On Nov 3, 2010, at 5:03 AM, Eric S Fraga wrote:

> Hello,
>
> short question as I seem to have got lost between the mailing list
> archives, the Worg documentation and the info files: does passing  
> header
> arguments when invoking a babel source code block using call or  
> function
> actually work?  it doesn't seem to for me for Ledger blocks (I've been
> trying to update the tutorial example) and I wonder whether I have  
> done
> something wrong with the ob-ledger code initially...
>
> Thanks,
> eric
>
> -- 
> : Eric S Fraga (GnuPG: 0xC89193D8FFFCF67D) in Emacs 23.2.1
> : using Org-mode version 7.02trans (release_7.3.10.g7f79.dirty)
>
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