[kde] Kmail filter to remove off topic stuff from mailing list

A mailing list is sending quite a lot of OT stuff, and I want to filter it out
with Kmail.

I've set up a filter to filter on subject line, then "contains", then just OT
in the blank box, but this isn't working properly.

For example, I'm getting mail like "Paypal Notice", and the filter is picking
up the "ot" in notice. Normally Bogofilter puts this stuff in the trash, but
is now being filtered out before it goes through Bogofilter.

What incantation is needed to just filter on the uppercase letters OT, that
are either at the start, or end of a subject line?

It doesn't help that some of these subject lines start with just OT, others
with OT: , and some with (OT).

I've already unsubscribed once from the Debian User list, but there is some
very usefull ontopic stuff, and from time to time I have been able to offer
help to someone. Removing the OT trash would help a lot.

Thanks for any suggestions.

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