help me, flist!!

[khana]

so, i'm in the process of subbing Ijon Tichy.

and i'm totally stumped by this:

"Sie sind Säuger, stimmts?"
"Ja, bin ich."
"Also schön, auf gutes Saugen."

first, tichy identifies himself s a mammal on a foreign planet.
and then, the customs officer wishes him "happy sucking". which makes sense and is funny because mammal is something like "sucker" in german.

so, i need some kind of play on "mammal".

any ideas?