Bug With nlobjSearchColumn and fields with same name

I am in the process of writing a script to return a customers last transaction. As part of the Transaction there are two child records being included, 'item' and a custom record 'custrecord1' which is joined by field 'custbody2'.
as part of the columns required in the return I need the interalid for both 'item' and 'custrecord1'. However which ever records field 'internalid' is added last, that is the once that is returned.

Here are two code samples and data returned. Key Fields are Bolden

Sample A:
var columns = new Array(  new nlobjSearchColumn("tranid",null),  new nlobjSearchColumn("trandate",null, null),  new nlobjSearchColumn("custbody7"),  new nlobjSearchColumn("memo"),    // Fields for custrecord1  <strong>new nlobjSearchColumn("internalid","custbody2", null),</strong>  new nlobjSearchColumn("name","custbody2", null),  new nlobjSearchColumn("custrecord27","custbody2", null),    // Item Fields  new nlobjSearchColumn("itemid","item", null),  <strong>new nlobjSearchColumn("internalid", "item", null),</strong>  new nlobjSearchColumn("class","item"),  new nlobjSearchColumn("custitem_itemtype","item")  );