Cauldron does not have ocaml libraries to read and write yaml. It's in Mandriva's svn, with a spec written by Florent Monnier (blue_prawn). http://svn.mandriva.com/cgi-bin/viewvc.cgi/packages/cooker/ocaml-syck/
Status: NEW => ASSIGNED
Ok it seems the syck library is no longer maintained, so this package is a bit useless. It has even been dropped from debian ...
Status: ASSIGNED => RESOLVEDResolution: (none) => WONTFIX