[Solved] Rad ComboBox Script Manager error

[Amit]

Hi,

I am working on Custom field type in MOSS 2007 (Sharepoint)
I am trying to add the RAD Combobox with treeview in one of the custom field types.
I am facing following issues:

1. If i put Script Manager tag in Master page,then i am not able to get the handle of radComboBox in code,it always returns NULL.
2. If i put Script manager tag in Template section of Custom field .ascx file it works fine,but this behivour fails if we want to use Rad Combobox in different field types and these field types are part of same page.
Error: Only one script manager tag allowed on one page.
3. I tried adding Script Manager tag in field type dynamically using following code snippet, but it still returns NULL for rad Combobox control.
 protected override void OnInit(EventArgs e)
        {
            ScriptManager sm = ScriptManager.GetCurrent(this.Page);
            if (sm == null)
            {
                sm = new ScriptManager();
                //add the ScriptManager as the first control in the Page.Form
                this.Controls.AddAt(0, sm);
            }
            base.OnInit(e);
        }

Any ideas on how we can add this Script Manager in one location say Master page and rad Combobox item still work fine??

Regards,
Amit