In general DEL-5.7/5.9 is only supported on development hosts running Ubuntu 10.04.1 or Ubuntu 12.04 as delivered on the installation/Live DVD by Digi. Digi will not support you with other Ubuntu versions or other distributions.
However for the particular case where Ubuntu 14 has no Qt3 anymore but only Qt4, we provide
in order to make DEL-5.7/5.9 graphical kernel configuration (xconfig) working. There is no support for any follow up questions on this, also additional compilation problems may occur, which you have to solve yourself.
After Ubuntu 12.04 LTS the libqt3-mt package was removed from the repositories. This package is needed for DEL's graphic config tool (make xconfig) so the tool fails due to the missing dependency.
In the kernel the Kconfig tool was migrated to QT4 at version 2.6.37, so we need to backport that version to DEL.
To apply the patch file del-1054-patch.diff do:
# cd /usr/local/DigiEL-5.9
# patch -p1 < del-1054-patch.diff