Hi,
Wrap attribute is depricated, it is better to use css rules (I think in your application there is a rule which turn off wrapping by default therefore we have different 'by default' behaviour)
See the following example
<%@ Page Language="C#" %>
<%@ Register Assembly="Coolite.Ext.Web" Namespace="Coolite.Ext.Web" TagPrefix="ext" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
<style type="text/css">
.wrap-area{
white-space:pre;
}
.nowrap-area{
white-space:nowrap;
}
</style>
</head>
<body>
<form id="form1" runat="server">
<ext:ScriptManager runat="server" />
<ext:TextArea runat="server" Width="100" Cls="nowrap-area"/>
<br />
<br />
<ext:TextArea runat="server" Width="100" Cls="wrap-area"/>
</form>
</body>
</html>