if you recieve the message:
UserWarning: Deliverance requires the CVS HEAD version of libxml2

this indicates the build has not properly built lxml to use the versions of libxml2 and libxslt 
that are included in this build. 

you should set your LD_LIBRARY_PATH to search the library directories under parts before 
your normal library paths, eg:

export DELIVERANCE_PATH="/your/buildout/path"
export LD_LIBRARY_PATH="$DELIVERANCE_PATH/parts/libxml2/lib:$DELIVERANCE_PATH/parts/libxslt/lib:$LD_LIBRARY_PATH"


you can check whether lxml is using the correct libraries by running 
ldd develop-eggs/lxml*egg/lxml/etree.so

libxml2 and libxslt should point within the buildout directory

This issue is noted in distutils bugs: 
https://sourceforge.net/tracker/?func=detail&atid=305470&aid=1254718&group_id=5470
https://sourceforge.net/tracker/?func=detail&atid=305470&aid=642019&group_id=5470
http://sourceforge.net/tracker/?func=detail&atid=105470&aid=445902&group_id=5470