sendmail strips +details from address

[Adam Williams]

>first let me say: in the basic configuration, that means 
>on a redhat box with cyrus deliver and sendmail 8.11.6
>everything runs fine.
>An email to an address like username+sub at ourdomain.com 
>reaches the folder sub of user username as expected.
>But since i've setup trendmicro interscan with sendmail
>in sandwich form, the +detail information got lost.
>All normal emailaddresses get the virusscanned email properly.
>Only a mail to username+sub at ourdomain.com drops into the 
>Inbox folder
>I think the problem is that any email has to pass sendmail 
>twice. This is part of the sandwich setup and i can see 
>this in the logfile. 
>Any suggestion how to tell sendmail not to strip +details?

You need to define the "preserve plus detail" feature in your m4 file
and regenerate sendmail.cf

See ftp://kalamazoolinux.org/pub/pdf/Cyrus.pdf for an example.