I don't know of any other open source alternatives, doesn't mean there aren't any, but I tried GnuCash which worked fine on my system but the export feature which is mission critical for us is non existant in GnuCash. KMyMoney is still some what lacking in features right now so we went to MoneyDance. It not free but it is reasonably priced and a full blown accounting system that exports, imports and runs on all OS's.