If Apache2 hangs, it could be because the system doesn't have enough entropy, which is needed by mod_auth_digest.
To check how much entropy you've got, run cat /proc/sys/kernel/random/entropy_avail. Apache2 needs > 100.
To generate more entropy you can run some system intensive task. One that's not mentioned in the above article is du /. Alternatively, /etc/init.d/rngd start will start the random number generator daemon. If it can find a hardward RNG then fine, but if not it will fall back to using /dev/urandom as it's input, which is not suitable for generating things like PGP keys (not random enough so not secure enough).
Reference
http://gentoo-wiki.com/Apache2_Install#Common_Problems (search for "Not Enough Entropy").