I am not aware of a way to do that. You can save a little time with the "Copy Settings" button under the "Projects" tab in the vault admin utility, but otherwise you'll need to set aside some time and hunker down. If you haven't already, you should consider assigning permissions by group to avoid a similar situation in the future.
The only way I know of is to set up the project folder first and assign the permisions there. Then creat all the subfolders after that has been done. The permissions should copy down to the sub folders from the main project folder. I would always use groups as PDMAdmin has stated.
If you have all the sub folders already set up then there is no way to do a gobal down to the sub folders that I know of.
