[horde] email filter for display-name

[Jens-U. Mozdzen]

Hi list,

I've been unsuccessful to create a filter based on the display-name  
part of the sender's email address.

Received emails have a "From: John Doe <someone at somewhere.com>" header  
line, with the actual e-mail address being ambiguous (I also receive  
mails with "From: Jane Doe <someone at somewhere.com>" headers).

When adding a filter on a "custom header" and set "From" as the header  
name, Ingo seems to automatically change this into an "address" filter  
in Sieve (if address :all :comparator "i;ascii-casemap" :contains  
"From" "John Doe"), but "address" only filters on the actual email  
address, not the display-name part included in the From: header.

How could I achieve the desired effect?

Regards,
Jens