SmartGWT paging problem with navigation(ToolStrip bar)

[jacoffee]

I have spend a whole day trying to do paging with navigation bar in SmartGWT.
As shown in the pic, when the page first load I wanna fetch the first 9 records(startRow 0, endRow 8), when click the nextPage button, listgrid will fetch next 9 (startRow 9, endRow 17)....
My problem is that How to control the startRow and endRow???

Info from MyEclipse..
criteria:{
startRow:27,
endRow:35
/*
the above number i achieve with the follow code

Criteria initPage = new Criteria();
initPage.addCriteria("startRow",(count-1)*PAGE_ROWS);
initPage.addCriteria("endRow",count*PAGE_ROWS-1);

*/
},
operationConfig:{
dataSource:"employeesinfo",
operationType:"fetch",
textMatchStyle:"exact"
},
startRow:0,
endRow:75,
/*
But the above two can be not changed???
*/
componentId:"isc_ListGrid_0",
appID:"builtinApplication",
operation:"employeesinfo_fetch",
oldValues:{
startRow:27,
endRow:35
}

Can anyone help, thanks!!!!!