This is a BUG with 2.0.3. The alternative is to use main.aspx: ..../Main.aspx?ACME

Thanks for the tip.  Until a fix is available I added the following to the top of Defaulst.aspx which seems to do the trick.

<script runat="server" language="C#">
override protected void OnInit(EventArgs e)
{
    base.OnInit(e);
    try
    {
        string url = Request.RawUrl;
        int pos = url.IndexOf('?');
        if (pos > 0)
        {
            url = "http://server/gemini/Main.aspx" + url.Substring(pos);
            Response.Redirect(url);
        }  
    }
    catch (Exception ex)
    {
        //
    }
}

Thanks for sharing this.

I think I was a little quick on that solution because it broke direct links to issues (http://server/gemini/Default.aspx?p=25&i=769)  I had to change it to the following. 

<script runat="server" language="C#">
override protected void OnInit(EventArgs e)
{
    base.OnInit(e);
    try
    {
        string url = Request.RawUrl;
        int pos = url.IndexOf('?');
        if (pos > 0 && url.IndexOf('=') < 0)
        {
            url = "http://server/gemini/Main.aspx" + url.Substring(pos);
            Response.Redirect(url);
        }  
    }
    catch (Exception ex)
    {
        //
    }
}
</script>

All I'll say is test it before putting it into production (I'm glad I did :)  If I have to make any further refinements, I'll post here.