form not into a dialog

form not into a dialog


jquery-1.3 + ui-jquery-1.6rc5
This code run perfectly with FF:
$("#creerDialog").dialog(
{
autoOpen:false,
width: 415,
height: 280,
position:"center",
title:"création d'un résident",
resizable:false,
buttons: {
"Sauver":function(){creation();$(this).dialog
('close')},
"Effacer":function(){$("#form1").each(function()
{this.reset();})}
}
});
<div id='creerDialog' style="display:none" >
<form action='' id='form1' >
...
</form>
</div>
But with IE7 the form part is not displayed into the dialog window
when I
press a button to open it.
If I move the dialog window, the form part cannot "catch" the dialog
window. Same phenomena when the browser window is reduced.
Any explanation ?