compile ios 6 error

7. Package for IOS:

     [echo] Packaging for IOS

     [java] [Fatal Error] :1:1: Content is not allowed in prolog.

     [java] java.io.IOException: PLIST generation failed due to SAX error:org.xml.sax.SAXParseException: Content is not allowed in prolog.

     [java]           at com.adobe.air.Plist.newFromString(Plist.java:280)

     [java]           at com.adobe.air.Plist.newFromFile(Plist.java:254)

     [java]           at com.adobe.air.ipa.IPAOutputStream.setSDKVersion(IPAOutputStream.java:919)

     [java]           at com.adobe.air.ipa.IPAOutputStream.setPlatformSDKLocation(IPAOutputStream.java:838)

     [java]           at com.adobe.air.ipa.IPAPackager.setDeviceSDKDirectory(IPAPackager.java:177)

     [java]           at com.adobe.air.ADT.parseFileAndPathArguments(ADT.java:1367)

     [java]           at com.adobe.air.ADT.parseDescriptorAndFileset(ADT.java:1418)

     [java]           at com.adobe.air.ADT.parseInput(ADT.java:902)

     [java]           at com.adobe.air.ADT.parsePackage(ADT.java:663)

     [java]           at com.adobe.air.ADT.parseArgsAndGo(ADT.java:563)

     [java]           at com.adobe.air.ADT.run(ADT.java:418)

     [java]           at com.adobe.air.ADT.main(ADT.java:468)

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