MIME decoding via metamail

I have played with using metamail as a preprocessor for ifile, that
is, to get metamail to decode attachments for me.  The following seems
to work:  Pipe each message through the command

        KEYHEADS='*' MAILCAPS=mailcap metamail -d 2>&1

(assuming korn-like shell), where "mailcap" is the file

        # All text is simply copied.
        text/*; cat %s
        # All other things are represented as "encodedinlined<type>"
        image/*; echo encodedinlined%t | tr -d -c '[:alpha:]'
        application/*; echo encodedinlined%t | tr -d -c '[:alpha:]'
        audio/*; echo encodedinlined%t | tr -d -c '[:alpha:]'
        message/*; echo encodedinlined%t | tr -d -c '[:alpha:]'

such that all headers and printable parts of the email will be output
on stdout, including decoding errors.  Unprintable parts are output as
a string

        encodedinlined<type>

where <type> is the MIME type, for example, 

        encodedinlinedimagejpg .

I am not sure about the message/* type (I just looked in my own
/etc/mailcap file).  Does anyone with a better understanding of
mailcap files have a better solution?  Why can't I write 

        *; echo encodedinlined%t | tr -d -c '[:alpha:]'

instead of repeating similar lines?
-- 
                                                    Jens Peter Secher
_____________________________________________________________________ 
 [email protected] - http://www.diku.dk/~jpsecher - (+45) 35 32 14 08
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