jQuery Grid Plugin - jqGrid

jqgrid 3.7.1

jquery 1.4.2

jquery ui 1.7.2

Just started using jqgrid -- overall working very well. My issue relates to cell edit functionality. Every column should be editable. That is fine. Certain rows should not be however based on a criteria.

I tried using the beforeEditCell callback function. I tried returning false from there but still the cell became editable when I clicked in it. Basically what I want is the text input to not even appear when I click on these particular cells.

Is there a particular callback I can use to achieve this? And what do I return from that to block the cell from turning into a text input?

Thanks.