xCode error on compiling for armv6 and 7 (Unity 3.5.7)

Hello,

I was updating one of our older games (made with Unity in 2011) and I am getting some errors while compiling for iOS:

I had to update the game's Unity project to run under 3.5.7 Pro (it was developed on a different Unity version)

Under player settings I have:

armv6+armv7 (I want all devices to get this update) SDK=latest Target version 3.1 No stripping of assemblies

I have tried compiling only for armv6, and the error goes away, but this game is supposed to run on all iOS devices. Also if it set this for armv6, it woun't run on my iphone5. The error I'm getting when I try to compile for armv6+armv7 is:

Undefined symbols for architecture armv7: "_OpenAppInAppstore", referenced from: RegisterMonoModules() in RegisterMonoModules.o ld: symbol(s) not found for architecture armv7 clang: error: linker command failed with exit code 1 (use -v to see invocation)

This seems to be one of Unity's libraries, am I correct? How can I fix this?

The game works well on all iDevices from '11 to current date.