I have created a UserControl that implements IWebPart but the title isn't being displayed.

string IWebPart.Title
        {
            get
            {
                if( m_Title != null )
                    return m_Title;
                else
                {
                    m_Title = "IWebPart, IWebActionable";
                    return m_Title;
                }
            }
            set
            {
                m_Title = value;
            }
        }

 I have tried it via code (above) and markup (below) 

<asp:WebPartZone ID="WebPartZone2" runat="server">
                        <ZoneTemplate>
                            <uc2:IWebActionable ID="IWebActionable1" Title="IWebPart, IWebActionable" runat="server" />
                        </ZoneTemplate>
                    </asp:WebPartZone>

Any ideas as to the problem?

I figured out the code behind for the user control and for the containing page.
Not sure when the html isn't working.

See my sample 

UserControl that implements IWebPart Interface

public partial class User_Controls_NewCalendar : System.Web.UI.UserControl, IWebPart

{
    public string CatalogIconImageUrl
    {
        get { return "images/calendar.JPG"; }
        set { return; }
    }

    public string Description
    {
        get { return "This is the description."; }
        set { return; }
    }

    public string Subtitle
    {
        get { return ""; }
    }

    public string Title
    {
        get { return "My Calendar"; }
        set { return; }
    }

    public string TitleIconImageUrl
    {
        get { return "images/calendar.JPG"; }
        set { return; }
    }

    public string TitleUrl
    {
        get { return "~/Default.aspx"; }
        set { return; }
    }

  
    protected void Page_Load(object sender, EventArgs e)
    {

    
    }

The just drag and drop the UserCOntrol in the WebZone and it will automatically displays the Title

<WebPartsTemplate>
        <uc1:NewCalendar ID="NewCalendar1" runat="server" />
</WebPartsTemplate>

that's what I'm saying.
The html way of setting the title isn't working.
The code-behind is working fine.

mpaterson:

The html way of setting the title isn't working.
The code-behind is working fine.

This should work

<ZoneTemplate>
          <uc5:TestUC ID="TestUC1" Title="A title" runat="server" />
</ZoneTemplate>

I know it should but it isn't.  Maybe it's because I have the WebPart.Title property in the UserControl?