Hidding rows

Hi all,
Thanks for you people support. I have a requirment f hidding rows and columns. For hidding columns i am using function
obj.setColumnIndices([1,3,4]);
It is working fine. but when i used the function
obj.setRowIndices([0,2,3,4]);
to hide rows, it is actually hidding rows, but at that hidding row position it is displaying white space. it is looking odd in my grid. will you please help any body to solve this problm