I'm getting the error db.h: No such file or directory when I try to build Exim.

This problem has been seen with RedHat_ 7.0, but could also happen in other environments. If your system is using the DB library, you need to install the DB development package in order to build Exim. The package is called something like db3-devel-3.1.14-16.i386.rpm for Linux systems, but you should check which version of DB you have installed (current releases are DB 4).

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