Instead of exim_dbmbuild, I'm using a homegrown program to build DBM (or cdb) files, but Exim doesn't seem to be able to use them.

Exim expects there to be a binary zero value on the end of each key used in a DBM file if you use the dbm lookup type, but not for the dbmnz lookup type or for the keys of a cdb file. Check that you haven't slipped up in this regard.

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