EXTJS: If entry has same title in combo

I have 2 accounts with same title my data is like

Account No           AccountTitle                 Town
===========          =============                =====
60                   Shahansha Flour Mill         MTN
64                   Shahansha Flour Mill         LHR 

When I show this data in a combo it shows me 2 entries for "Shahansha Flour Mill" (correctly) but whatever I select it always selects the first one with account no 60, whether I select the first entry or the second. How can I resolve this issue?

i found soln on this thread http://www.sencha.com/forum/showthread.php?91252-FIXED-525-Combo-submits-wrong-value-if-displayField-has-same-entries