Digest not digesting well with Ocra? :P

Bad pun? Never mind. I’m having problem with using digest on any .exe
produced from ocra.

version = Ocra 1.3.3

Here is a simple text to md5 in Ruby which fails to execute from .exe
but runs successfully as .rb

http://pastebin.com/CVJdBun6

Here is the error I get when executing

C:\Users\w4r10ck\Desktop>qa.exe

C:/Users/w4r10ck/AppData/Local/Temp/ocr36DB.tmp/lib/ruby/2.0.0/digest.rb:12:in
const_missing': library not found for class Digest::MD5 -- digest/md5 (LoadError) C:/Users/w4r10ck/AppData/Local/Temp/ocr36DB.tmp/src/qa.rb:7:inblock
in ’
C:/Users/w4r10ck/AppData/Local/Temp/ocr36DB.tmp/src/qa.rb:3:in loop' C:/Users/w4r10ck/AppData/Local/Temp/ocr36DB.tmp/src/qa.rb:3:in

One last question which might not be relevant to this question.
What’s the difference between
require ‘digest’ and require ‘digest/md5’