Double scrollbars in Qtoolbox

I use a toolbox and I push in QTextEdit as items with the method addItem. So one open toolbox slot contains a QTextEdit and for some reason already a scrollbar. This scrollbar is not neccessary since the QTextEdit automatically adds a scroll bar a soon as the text goes beyond the open toolbox slot. The result is double scroll bars, one on the toolbox item that is always visible one that is added by the textedit. How can I disable the default toolbox-items-scrollbars and only let the textedit add a scroller? Thanks