Hide '+' sign in DataGrid 2.0

Question

When displaying in a DatGrid an ArrayList of objects that contains a collection of objects itself, I get a '+' sign in every row that shows the content of the collection. Is there anyway to get rid of the '+' sign, o at least assign a DataGridTableStyle to the dataGrid when it shows the child collection? To display the ArrayList in the dataGrid Im assigning it to the property DataSource of the DataGrid.