txin.rb in bitcoin-ruby-0.0.3

- old
+ new

@@ -29,9 +29,11 @@
       COINBASE_INDEX = 0xffffffff
 
       def initialize *args
         @prev_out, @prev_out_index, @script_sig_length,
         @script_sig, @sequence = *args
+        @script_sig_length ||= 0
+        @script_sig ||= ''
         @sequence ||= DEFAULT_SEQUENCE
       end
 
       # compare to another txout
       def ==(other)