Yes, I received it, thank you.

Well, it does look like your Xcode project file is bogus. See line 126:

% Unity-iPhone.xcodeproj\project.pbxproj
		702641D8836EE483395489CD /* null.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 60A34832B960B3FC7D3B0D6C /* null.framework */; };
%

So, it turned out the builder isn't inventing it... the Xcode project file does mention a framework called "null", which it claims can be found among the default iOS frameworks. The problem is, to my knowledge, no such framework exists.

I think you should report this error to the Unity team.