I`m unable to select text from a extjs grid textbox from keyboard
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I have a extjs dashboard(grid) with a textbox,if i enter text in it and if i have delete it ,i have to press backspace button to erase.Problem is i`m unable to select it by pressing 'shift+leftarrow' to delete it.How can I accomplish it.I`m using extjs 3,and i have IE8.
Plz help...Following is my code ->

    <img alt=''  src='../Images/image.gif' onClick='function();' style='width:15;float:right;cursor:pointer'></img><input type='text' id='idea' style='width:300;float:right' class='x-form-text' type='text' onKeypress='keypress()'></input>