Keywords: destinationspamfilterXoptin, sourcespamfilterXoptin
destinationspamfilterXoptin specifies that all messages destined to this channel are run through filtering software X. (Filtering software X is defined by spamfilterX_library in option.dat.) The filter parameters follow the keyword and the available parameters depend on the filtering program.
sourcespamfilterXoptin specifies that all messages originating from this channel are run through filtering software X. (Filtering software X is defined by spamfilterX_library in option.dat.) The system-wide default parameters follow the keyword and the available parameters depend on the filtering program. If switchchannel is in effect, this keyword is placed on the switched-to channel.
For complete details on how these keywords are used, see To Specify Channel-level Filtering.