Hide New Button in Lookup dialog od lookup field crm2011 online

Dear all,

I now have a lookup field on form.

And I want that when i click on lookup field -> the lookup is opened without New button.

In the past use:

           var beneficiaryLookup = crmForm.all.core_beneficiaryid;
            beneficiaryLookup.AddParam("ShowNewButton", "0");

And its work.

But currently Im test on organization online and it not work, it said that AddParam is undefined.

Any idea for it, please?

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