Just my thoughts about your "convert alpha mnemonics":

# convert alpha mnemonics
$phone =~ tr/A-Za-z/2223334445556667Q7788899992223334445556667q7788899
+99/;
[download]

is a bit shorter ;-) and does it in one run. BTW: On german phones you'll find the Q on 7. So Germans should replace Q and q above with 7.

Question: Did you forget the last 9 (9999 for wxyz) in your code?