CLIENT-BODY-FILTER: blafasel-to-bumfidel Changes "blafasel" to "bumfidel"
s@blafasel@bumfidel@

CLIENT-BODY-FILTER: bumfidel-to-tralala Changes "bumfidel" to "tralala"
s@bumfidel@tralala@

CLIENT-BODY-FILTER: empty-body Only applies to empty content bodies
s@^$@empty-body detected that there was no data@