jQuery Grid Plugin - jqGrid

Hi Guys 

Currently we are using jqGrid with a custom jquery ui theme. I want to know is there a way we can keep the jquery ui theme for our dialog and such but have jqGrid use another custom css file that we create. It seems to me that if the jquery ui css file is found then jqGrid automatically defaults to that but we want it to use a custom css file. To sum it all up does jqGrid have a hard dependency on the jquery ui css file and second can we specify our own css file. Any help would be much appreciated

thanks