Updating to version 2.6.9:
"Many things have changed. Bugs have been fixed, new features
have been introduced. But most importantly, we're really retiring
the old 1.x-style libpqxx API now. This API (where upper-case letters
were still used in function names and such) has been supported for
more than three years in the interest of backwards compatibility,
but has been marked as obsolete all this time."