bank certificate

my wife is applying for Tourist Visa going to Beijing and meet all the requirements (round trip ticket, hotel reservation in Crowne Plaza Hotel in Beijing, etc...), but for the Bank Certificate, its 3rd time that they (Visa Officers) denied the Visa, as for the Bank Certificate format they want is from Metrobank and our Bank is BDO in which they have their own Bank Certificate format for Visa application, stated clearly in 6 motnhs Bank Certificate,we deposited of more than 100K monthly and the current account is more than 100K.
I can not understand why they (Visa Officers) want the Metrobank format, but our bank is BDO and the BDO personnel told my wife that, how come that BDO Bank Certificate format is not acceptable in Tourist Visa application as it is the same Bank Certificate that they are issuing for Visa application.
I`m here in Abu Dhabi in UAE and already obtain my Tourist Visa here in China Embassy in Abu Dhabi.
Our trip is on 31 August 2012 - 02 September 2012 for 3D/2N travel tours provided by Xian Marco Polo International Travel Services Co.,Ltd.