Not sure if this is what you're hitting, but it looks like evolution 2.10.1 was built with gnome-doc-utils 0.10.2, which has a serious bug that causes the build to fail when you try to compile with scrollkeeper disabled [1].
Thank you for the tip, but I'm building with gnome-doc-utils 0.10.1 (and with scrollkeeper enabled, wich is the default choice made by ./configure). I tried with gnome-doc-utils 0.10.3 : still same "db2omf: Could not construct the OMF subject element" bug. But thank you all the same. Nicolas (France)