Problem with ANE - "ld: -pie can only be used when targeting iOS 4.2 or later"

I'm trying to compile a simple AIR Mobile app for iOS, incorporating an ANE to support Localytics

http://flashsimulations.com/2012/06/18/localytics-adobe-air-native-ext ension/

Compilation fails with the message "ld: -pie can only be used when targeting iOS 4.2 or later"

Surely 7.0 is later than 4.2! (I'm using Flex 4.6 - AIR 3.9 SDKS). Tried building with FDT and with Flash CC, and against earlier versions of the iOS SDK (6.0, 5.0).

Any suggestions?