disable local_scan fro bounces

Hi all,

I'm actually receiving a lot of bounce due to spam with mail from of one
of my domain.

Problem is that spamassassin is launched on each of this (bad) mails and
the load on my machines are too high and I'm queuing a lot.

Is there a way to disable sa-exim for that type of message.

I believe I should do somethin in SAEximRunCond but I didn't any
suitable string yet.

Thanks for your help.

Laurent.
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