The remaining problem is not easy to fix because
python2.5/2.6 and 2.7 behave differently. :/
One creates continuation lines with ' ' (2.7.) and the other with '\t'.

See http://bugs.python.org/issue1974
and https://hg.python.org/cpython/rev/5deb27042e5a 

This means we also get differnent behaviour when writing emails
with roundup running on either 2.5/2.6 or 2.7. :/