Something

install_pkgs() (
        PACKAGES="lighttpd-1.4.18_1 php5-5.2.4_1"
        export PACKAGESITE="ftp://127.0.0.1/"

        # add an alias to /etc/hosts in our world dir to fix pkg_add stupidity
        cp -pf "${NANO_WORLDDIR}/etc/hosts" "${NANO_WORLDDIR}/etc/hosts.orig" && \
                echo "127.0.0.1         All" >> "${NANO_WORLDDIR}/etc/hosts"

        # perform the installation by chrooting and going at it
        for package in $PACKAGES
        do      pkg_add -C "${NANO_WORLDDIR}" -r "${package}"
        done

        # restore the original /etc/hosts
        mv -f "${NANO_WORLDDIR}/etc/hosts.orig" "${NANO_WORLDDIR}/etc/hosts"
)