editor.EnableTab = true;

function IsPluginChecked( sPluginName )
{
	for( nID = 5632; nID <= 5632 + 255; nID++ ){
		str = editor.QueryStringbyID( nID );
		if( str == sPluginName ){
			nStatus = editor.QueryStatusByID( nID );
			if( nStatus & eeStatusLatched ) {
				return true;
			}
			break;
		}
	}
	return false;
}

alert( IsPluginChecked( "OpenDocuments.dll" ) );