All of my custom web parts in SPS 2003 use .ascx
controls with 1.1 DataGrids. In MOSS, I want to use
the SPGridView instead of a 1.1 DataGrid to make it
look more MOSS-like.

I was able to figure out how to drop a SPGridView onto
a .ascx control. However, when I attempt to modify
any properties thru the designer, I receive the
following error:
Cannot create an object of type
'Microsoft.SharePoint.WebControls.SPMenuField' from
its string representation 'SPMenuField' for the
'GroupMenu' property.

I can programmatically access a SPMenuField from
within code. However, I cannot add a SPMenuField onto
my Toolbox.