Can't select certain rows in datagrid

Question

Hello,
    I have a datagrid with 3 columns, that works great until you have 2 rows next to each other w/ the exact first name and last name.
When that happens, I can select the top row but I can't select the bottom row.
If I trace the onPatientSelected method, it never gets called.
here's my datagrid code below: 
<code>
            <mx:DataGrid
                id="patientList"
                dataProvider="{dataProvider}"
                change="onPatientSelected()"
                styleName="patientlist"
                width="100%"
                height="100%"
                editable="false"
                draggableColumns="false"
                resizableColumns="false" headerRelease="checkColumnSorted(event)">
                <mx:columns>
                    <mx:DataGridColumn headerText="Last Name"  dataField="LastName" />
                    <mx:DataGridColumn headerText="First Name" dataField="FirstName"/>
                    <mx:DataGridColumn headerText="Unique Id" dataField="UniqueId" sortable="false"/>
                </mx:columns>
            </mx:DataGrid>
</cod> 
Any ideas?

Answer 1

The strange thing is that we have datadrids all over this app that are formatted exactly the same way and this behavior never happens:
Here's another example:
<code>
<mx:DataGrid
                id="contactDataGrid"
                change="onItemSelected()"
                styleName="patientlist"
                width="50%"
                height="100%"
                editable="false"
                draggableColumns="false"
                resizableColumns="false" >
                <mx:columns>
                    <mx:DataGridColumn headerText="Name" dataField="FirstName" />
                    <mx:DataGridColumn headerText="Relationship" dataField="RelationshipToPatientTypeId"/>
                </mx:columns>
            </mx:DataGrid>
</code>