Just a thought but it seems BTCe is broken by design. Their API spec shows only limit orders, and xchange sends only market orders. This causes the following error it appears.
java.lang.UnsupportedOperationException: Market orders not supported by BTCE API.
at com.xeiam.xchange.btce.service.trade.polling.BTCEPollingTradeService.place
MarketOrder(BTCEPollingTradeService.java:68)
Possibly altering the order to actually complete by making it a limit order would be great.
All exchanges in XChange also have a placeLimitOrderMethod.