Default Button Property

Hi,

I am using Default Button Property of a panel  which by default clicks some button (say B1) on pressing Enter Key but the problem is that if i come to some other Button(say B2) by tabbing and press enter, the same old button(B1) gets clicked, which is correct otherwise(because both buttons are inside same panel).

I cant remove any of these two buttons out of the panel. Is there any other way to set default button on Enter key. I have tried Javascripts also but facing the same problem.
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