iOS: Photon Realtime 4.1.4 link error using Xcode 8.1 and libstdc++

Hi!

I'm trying to link my proprietary game engine with Photon Realtime SDK v 4.1.4.0.
I'm using Xcode 8.1, target platform iOS, planning to upgrade to Xcode 8.2 soon. Added some test source and Photon libraries but got link errors:
"std::__1::mutex::~mutex()", referenced from:
__GLOBAL__sub_I_PeerBase.cpp in libPhoton-cpp_release_iphoneos.a(PeerBase.o)
"std::__1::mutex::lock()", referenced from:
ExitGames::Photon::Internal::PeerBase::serviceBasic() in libPhoton-cpp_release_iphoneos.a(PeerBase.o)
ExitGames::Photon::Internal::PeerBase::onPingResponse(ExitGames::Common::JString const&, unsigned int) in libPhoton-cpp_release_iphoneos.a(PeerBase.o)
"std::__1::mutex::unlock()", referenced from:
ExitGames::Photon::Internal::PeerBase::serviceBasic() in libPhoton-cpp_release_iphoneos.a(PeerBase.o)
ExitGames::Photon::Internal::PeerBase::onPingResponse(ExitGames::Common::JString const&, unsigned int) in libPhoton-cpp_release_iphoneos.a(PeerBase.o)
ld: symbol(s) not found for architecture arm64

I see it can't find std::mutex, I using libstdc++ (=NO C++11 allowed) that's why. But I need to use libstdc++, all my third-party libraries are linked to it. Also game engine will likely break if I somehow change C++ standard library to libc++.
So, please could You support libstdc++, better to have some hot fix for 4.1.4.0 or if it's difficult, I may switch to newer Photon SDK.

I hope to see Your solution for such easy problem soon, and then I can use Your SDK, thanks!