Calibre converts, but don't works fine with TOC for me. Now I use several tools (Sigil and others).
Mi goal is a free Word Processor (OpenOffice) and save or export to ePub.
NOTE: Now I discover than writer to ePub create TOC (0.3.5 version), but
Adobe Digital Editions crash when I try to open the file. I repair this with Sigil. I'll will continue in their thread. Thanks for all