Custom control: where to put control class?

Hi all..
a quick question.

I'm building a custom control "imagePicker", that wants to select an 
image from repo..

My question is: is it possible to user a different package than 
info.magnolia.cms.gui.dialog? In this case the constructor shold be 
public, and not protected as some examples...

There could be any problem related to the Factory?

Thanks!!
Matteo

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