Disable DataGridView Combobox cell   

I have a databound DataGridView which has five columns and two of which are 
ComboBox columns. I want to disable one combobox cell in a row depending 
upon the selection in the other combobox cell. I cannot find a way to 
disable the Combobox cell for a row in a grid.

Any help would be appreciated.
Thanks

date: Thu, 17 Jul 2008 22:50:51 -0500   author:   Bofors am