NSURLConnection crush on iOS6

When you using NSURLConnection on iOS6 and receive header field "WWW-Authenticate", It must have realm params like 「WWW-Authenticate:OAuth realm="xxxx"」.
Otherwise it will crash.

CFNetwork`CFURLProtectionSpaceGetAuthenticationScheme:
0x45497be:  pushl  %ebp
0x45497bf:  movl   %esp, %ebp
0x45497c1:  subl   $8, %esp
0x45497c4:  calll  0x4549220                 ; URLProtectionSpace::Class()
0x45497c9:  movl   8(%ebp), %eax
0x45497cc:  movl   40(%eax), %eax
0x45497cf:  addl   $8, %esp
0x45497d2:  popl   %ebp
0x45497d3:  ret

I already sent bug report to apple.