when host system use utf-8 encoding, ssh fails.

oid  "\x06\t*\x86H\x86\xF7\x12\x01\x02\x02"  #<Encoding:ASCII-8BIT>
supported_oid  "\u0006\t*\x86H\x86\xF7\u0012\u0001\u0002\u0002"   #<Encoding:UTF-8>

'if oid != supported_oid' give the wrong result.

force encoding with ASCII-8BIT fix the problem.