I have modified the MultiCell method, it works as the above answer, and you can use the method in the same way as the Cell method.
function MultiCell($w, $h, $txt, $border=0, $ln=0, $align='J', $fill=false)
{
    // Custom Tomaz Ahlin
    if($ln == 0) {
        $current_y = $this->GetY();
        $current_x = $this->GetX();
    }
    // Output text with automatic or explicit line breaks
    $cw = &$this->CurrentFont['cw'];
    if($w==0)
        $w = $this->w-$this->rMargin-$this->x;
    $wmax = ($w-2*$this->cMargin)*1000/$this->FontSize;
    $s = str_replace("\r",'',$txt);
    $nb = strlen($s);
    if($nb>0 && $s[$nb-1]=="\n")
        $nb--;
    $b = 0;
    if($border)
    {
        if($border==1)
        {
            $border = 'LTRB';
            $b = 'LRT';
            $b2 = 'LR';
        }
        else
        {
            $b2 = '';
            if(strpos($border,'L')!==false)
                $b2 .= 'L';
            if(strpos($border,'R')!==false)
                $b2 .= 'R';
            $b = (strpos($border,'T')!==false) ? $b2.'T' : $b2;
        }
    }
    $sep = -1;
    $i = 0;
    $j = 0;
    $l = 0;
    $ns = 0;
    $nl = 1;
    while($i<$nb)
    {
        // Get next character
        $c = $s[$i];
        if($c=="\n")
        {
            // Explicit line break
            if($this->ws>0)
            {
                $this->ws = 0;
                $this->_out('0 Tw');
            }
            $this->Cell($w,$h,substr($s,$j,$i-$j),$b,2,$align,$fill);
            $i++;
            $sep = -1;
            $j = $i;
            $l = 0;
            $ns = 0;
            $nl++;
            if($border && $nl==2)
                $b = $b2;
            continue;
        }
        if($c==' ')
        {
            $sep = $i;
            $ls = $l;
            $ns++;
        }
        $l += $cw[$c];
        if($l>$wmax)
        {
            // Automatic line break
            if($sep==-1)
            {
                if($i==$j)
                    $i++;
                if($this->ws>0)
                {
                    $this->ws = 0;
                    $this->_out('0 Tw');
                }
                $this->Cell($w,$h,substr($s,$j,$i-$j),$b,2,$align,$fill);
            }
            else
            {
                if($align=='J')
                {
                    $this->ws = ($ns>1) ?     ($wmax-$ls)/1000*$this->FontSize/($ns-1) : 0;
                    $this->_out(sprintf('%.3F Tw',$this->ws*$this->k));
                }
                $this->Cell($w,$h,substr($s,$j,$sep-$j),$b,2,$align,$fill);
                $i = $sep+1;
            }
            $sep = -1;
            $j = $i;
            $l = 0;
            $ns = 0;
            $nl++;
            if($border && $nl==2)
                $b = $b2;
        }
        else
            $i++;
    }
    // Last chunk
    if($this->ws>0)
    {
        $this->ws = 0;
        $this->_out('0 Tw');
    }
    if($border && strpos($border,'B')!==false)
        $b .= 'B';
    $this->Cell($w,$h,substr($s,$j,$i-$j),$b,2,$align,$fill);
    $this->x = $this->lMargin;
    // Custom Tomaz Ahlin
    if($ln == 0) {
        $this->SetXY($current_x + $w, $current_y);
    }
}