Suppress delivery-notification/Read-receipt for spam?

[Ralf Hildebrandt]

The good news: amavis/SA recognized a piece of spam and tagged it
accordingly.

The bad news: The mail was delivered, and then a read-receipt (in this
case "not read") was sent back to the spammer.

Can this be suppressed somehow?

-- 
Ralf Hildebrandt                   Charite Universitätsmedizin Berlin
ralf.hildebrandt at charite.de        Campus Benjamin Franklin
https://www.charite.de             Hindenburgdamm 30, 12203 Berlin
Geschäftsbereich IT, Abt. Netzwerk fon: +49-30-450.570.155