Can Somebody please explain an issue I am facing with Apex properties.

I have a combo box(in visualforce). Following is the code for the combobox:-





In Apex I've given below two sets of code
1) New Properties:- property made according to Apex Script 13.0.
2) Old Properties:- property made according to scripts older than Apex Script 13.0.

###############################################################################
//------------------------- New Properties ----------------------------------
public String CurrencyMaster
{
get { return this.m_currencyMaster; }
set { this.m_currencyMaster=value; }
}
//-----------------------------------------------------------------------------

//------------------------- Old Properties ----------------------------------
public String getCurrencyMaster() { return m_currencyMaster; }

public void setCurrencyMaster(String value) { m_currencyMaster = value; }
//-----------------------------------------------------------------------------
###############################################################################

Now, the problem is that I am successfully getting the value of selected item in case of "Old Properties" but if I use "New Properties", its value doesn't gets set. It gives me a Null value.

Please Explain????

Thanks in Advance.

A.V.