jQuery Grid Plugin - jqGrid

hi all!

I'd like to use jqgrid in a project which is used to manage permission and roles. to display the setting, I'd like to have a row for each permission configured in the system. a permission may give access to anything for any role configured. the grid should look like:

permission | role 1 | role 2 | role 3 | role 4

________________________________

permi. 1        yes       no       yes       no

________________________________

permi. 2        no        no       yes      yes

The problem is now that I'd like to add columns (roles) depending on the answer I get from the server. How may I do this to achieve the following after a request?

permission | role 1 | role 2 | role 3 | role 4 | role 5 | role 6

___________________________________________

permi. 1        yes       no       yes       no       no        yes

___________________________________________

permi. 2        no        no       yes      yes       no        yes

Thanks for your answer.

michael