function OpenXML_Rels_ReplaceTarget($RelsPath, $OldTarget, $NewTarget) {
	
		$idx = $this->FileGetIdx($RelsPath);
		if ($idx===false) $this->RaiseError("Cannot edit target in '$RelsPath' because the file is not found.");
		$txt = $this->TbsStoreGet($idx, 'Replace target in rels file');
		
		$att = 'Target="'.$OldTarget.'"';
		$loc = clsTbsXmlLoc::FindStartTagHavingAtt($txt, $att, 0);
		if ($loc) {
			if ($NewTarget === false) {
				$loc->Delete();
			} else {
				$loc->ReplaceAtt('Target',$NewTarget);
			}
			$this->TbsStorePut($idx, $txt);
			return true;
		} else {
			return false;
		}
	
	}