function clearFormField(frm, fld, dft){
	if (document.forms[frm].elements[fld].value == dft)
		{
		document.forms[frm].elements[fld].value = '';
		}
}

function blocking(nr, img)
{
	if (document.layers)
	{
		if (document.layers[nr].display == 'none')
		{
		document.layers[nr].display = 'block';
		document.images[img].src = icn_minus.src;
		}
			else
		{
		document.layers[nr].display = 'none';
		document.images[img].src = icn_plus.src;
		}
	}
	else if (document.all)
	{
		if (document.all[nr].style.display == 'none')
		{
		document.all[nr].style.display = 'block';
		document.images[img].src = icn_minus.src;
		}
			else
		{
		document.all[nr].style.display = 'none';
		document.images[img].src = icn_plus.src;
		}
	}
	else if (document.getElementById)
	{
		if (document.all[nr].style.display == 'none')
		{
		document.getElementById(nr).style.display = 'block';
		document.images[img].src = icn_minus.src;
		}
			else
		{
		document.getElementById(nr).style.display = 'none';
		document.images[img].src = icn_plus.src;
		}
	}
}

function jump_chck(idskup_prod, nr, img)
{
	if (document.forms['jump_form'].elements[nr].value == 0)
	{
		document.forms['jump_form'].elements[nr].value = idskup_prod;
		document.images[img].src = icn_chckd.src;
	}
		else
	{
		document.forms['jump_form'].elements[nr].value = 0;
		document.images[img].src = icn_unchckd.src;
	}
}

function reg_chck(nr, img)
{
	if (document.forms['registrace'].elements[nr].value == 0)
	{
		document.forms['registrace'].elements[nr].value = 1;
		document.images[img].src = icn_chckd_w.src;
	}
		else
	{
		document.forms['registrace'].elements[nr].value = 0;
		document.images[img].src = icn_unchckd_w.src;
	}
}

function cnd_chck(new_idl)
{
	var nr = 'LOGISTIKA';
	var cur_idl = document.forms['registrace'].elements[nr].value;
	document.images['log_rdo_'+cur_idl].src = icn_unchckd_w.src;
	document.forms['registrace'].elements[nr].value = new_idl;
	document.images['log_rdo_'+new_idl].src = icn_chckd_w.src;
}