How to set one region over the other (and not beside it) in Omega theme? I´m using Omega theme in a Drupal 7 installation, and don´t know how to put the sidebar second right below the sidebar first.

Under Zone and region configuration I have the content section, with the content zone inside it.
Content zone has 12 columns.
Inside it I have 2 regions:
content (6 cols).
sidebar second (3 cols).

If I add there another region, (sidebar first in my case) Omega puts it along the other two, and I can only set the weight of each one to determine wich one will appear first.
But what if I want one region under the other?

I´m using delta module to create different layouts according to some variables, but every time I try to set one region over the other it fails. Is there any way to do that?

Thanks!



UPDATE: How may I use context to do that in case it is possible?
The side bars are used to create columns and not for placing it one on top of the other.

If you want a single column then you would go for one of the three. If you want two columns go with any two of them and if you want three columns go for all three. 

As for placing contents one on top of the other the blocks should be used for that. Let us say you have two blocks one to show the latest articles and another to place the login box and you want the articles to be on top of the login box then you would go with one of the side bars and content and place both the blocks in the same sidebar and arrange it as you would want it.