Reusing controls on fieldsets

[Ivan Furdi]

Hello again,

I would like to know how to reuse a control on multiple fieldset and if 
that is even possible?

Example :

I have a tabbed panel with 2 tabs with forms on each tab. Each form 
contains one fieldset with some fields.
One query select field is common for both fieldsets and I add it during 
onInit() method to the first fieldset but i
cannot add it to the second one too - if I do such a thing it just 
changes the parent and its not added on first one.

Any suggestions?

Ivan