Here's mine. The table and shifting should be right.

Code:

function vigenere($t,$k,optional $d)
   dim $j,$r,$,$p,$o,$m,$y
   for $j = 65 to 90
      $ = chr($j)+$+chr($j+32)
   next
   $p = "0123456789"+$
   $m = 62 - (ucase($t+$k)=$t+$k)*26
   for $j = 1 to len($t)
      do 
         $ = left($k,1)
         $k = substr($k,2)+$
         $ = instr($p,$)
      until $
      $y = substr($t,$j,1)
      if instr(".!? ",$y)
         $o = ($y=" ")*($o+1)
      endif
      $r = instr($p,$y)
      $vigenere = $vigenere + iif($r,substr($p, (iif($d,$m-$,$)+$r+o-1) mod $m+1,1),$y)
   next
endfunction
_________________________
Eric