invalid multibyte char on ubuntu 14.04

[cweiske]

On Ubuntu 14.04 I got the following error when trying to use spark-ping:

./spark-ping 192.168.22.1
./spark-ping:42: invalid multibyte char (US-ASCII)
./spark-ping:42: invalid multibyte char (US-ASCII)
./spark-ping:42: syntax error, unexpected $end, expecting keyword_end
  ticks=%w[▁ ▂ ▃ ▄ ▅ ▆ ▇]
             ^

Ruby:

$ ruby --version
ruby 1.9.3p484 (2013-11-22 revision 43786) [x86_64-linux]