Compile SampleApp Error in Xcode6.1 - already follow in sticky

I use version  3.0.9 of the IOS SDK on Xcode6.1 , and do instruction follow by this sticky https://developer.vuforia.com/forum/ios/ios-8-xcode-6-and-vuforia-30-compatibility

but still compile error  

Undefined symbols for architecture armv7:

  "vtable for std::basic_stringbuf<char, std::char_traits<char>, std::allocator<char> >", referenced from:

      l10746 in libVuforia.a(libVuforia.a-armv7-master.o)

      l10757 in libVuforia.a(libVuforia.a-armv7-master.o)

      l10801 in libVuforia.a(libVuforia.a-armv7-master.o)

  NOTE: a missing vtable usually means the first non-inline virtual member function has no definition.

  "VTT for std::basic_istringstream<char, std::char_traits<char>, std::allocator<char> >", referenced from:

      l10746 in libVuforia.a(libVuforia.a-armv7-master.o)

      l10757 in libVuforia.a(libVuforia.a-armv7-master.o)

      l10801 in libVuforia.a(libVuforia.a-armv7-master.o)

...

..

.

Anyone knows what am i missing?

Thanks you.