I can't get a border to show around a dijitMenuItem. I thought adding the following to the class ".tundra .dijitMenuItem" should work, am I mistaken?

I need to use a grid on a page for displaying data after a query.
If i use the grid in an empty page it works fine, but i need to put it inside a contenpane that is inside a tabcontainer.
The problem is that the grid doesn't load the data, the rows are displayed only when i scroll down with the mouse whell.
Searching in the html code i noticed that the data isn't loaded at all, and not only hidden as i tought at first.

How can i force the loading of the data?
I'm searching to replicate what appens when i scroll down, it can be a solution, but i haven't found anything yet..