Thread+Scope+Null Reference = HELP

hi,

i want to ask smt about databinding, threading etc.

this is situation:

lets say: i have a type dataset (name: "dsall")
it has datatables table1 , table2
threre are adapters which fills these and ,datagrids etc which is
databounded to this dataset

then i write this code to FORM_LOAD

//create thread in order not to wait getting process

private void formload(.......,.....)
{

Thread thr =new Thread(new ThreadStart(xx));
thr.isBackGround = true;
thr.Start();

//other things
}

private void xx()
{
adapter1.Fill(dsAll.Table1);
adapter1.Fill(dsAll.Table2);
//etc etc..
}

here is problem
when this code is executed, Null Reference exception is thrown

as i understand adapter1 creates datatable in thread scope and because
thread is ended, garbage collector collects datatable so i get null
reference exception, i say this because if i use this form there is no
error.

private void formload(.......,.....)
{

//dont use thread
//Thread thr =new Thread(new ThreadStart(xx));
//thr.Start();
//call directly function
xx();

//other things
}

but i need to fill dataset with thread

Thanks in advance

Erdem...