Ruby JSON protocol uses pack('m') method to encode Base64 string.
It seems that it inserts a "\n" character every 60 characters.
You can refer to these pages for this behavior.
Line feeds are added to every 60 encoded characters.
This has been making it impossible to send long binary field data to other languages.
I fixed this by using alternative encode method that is added in Ruby 1.9 (which should be OK).
After the fix, I had to add Ruby namespace to DebugProtoTest.thrift to avoid name collision of "Base64" symbols that is used for new encode method and also as DebugProtoTest message name.
I also removed extraneous double quote in encoded binary fields that resulted in invalid JSON.