Shell Programming and Scripting

I need to have my scripts import volume groups and mknod devices files. I have most of the script working but the device file needs to be in the format 0x??0000 (where the question marks are my HEX representations of the volume group number. I have the code below and the output it produces which would work great except anything that is only one charater will not work (I.E "1" needs to be "01", "a" needs to be "0a"). Any suggestions? And I can't use any perl code.

#!/bin/sh

for y in vg01 vg02 vg03 vg10 vg21 vg22 vg23
do
printf "%#x\n" $(echo ${y} | sed 's/^vg//') | sed 's/0x//'
done



Output:

1
2
3
a
15
16
17

Code:

for y in vg01 vg02 vg03 vg10 vg21 vg22 vg23
do
printf "%02x\n" ${y##*[a-zA-Z]}
done

That worked great thank you