The packages built from the glibc sources are critical. [1] Don't update those without applying the changes that make them compatible with kernel 2.6.28! [2] Otherwise ED won't start.
(btw: This is also the showstopper that prevented me from updating ED to Stretch. glibc has seen a major rewrite between the versions in Jessie and Stretch, and I've never figured out if or how support for kernel 2.6.28 can be patched in again.)

The pulseaudio packages [3], while not being critical for the system to run, need to be rebuilt to use the protocol version of Maemo's old pulseaudio version. [2] Otherwise you'll have no sound in ED.


[1] https://packages.debian.org/source/jessie/glibc
[2] http://talk.maemo.org/showpost.php?p...postcount=3138
[3] https://packages.debian.org/source/jessie/pulseaudio