Packaging for android on linux using flex sdk 4.6 gives "aapt: cannot execute binary file"

I created a very simple flex application "HelloWorld.mxml".

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark">
<s:Button label="Hello World!" />
</s:Application>

After building the swf file, I try to package it for deployment on my Android tablet.

adt -package -target apk -storetype pkcs12 -keystore newcert.p12 HelloWorld.apk HelloWorld-app.xml HelloWorld.swf

After entering the certificate password I receive this error message:

aapt tool failed: /opt/flexsdk4.6/lib/android/bin/aapt: /opt/flexsdk4.6/lib/android/bin/aapt: cannot execute binary file

Packaging the app in Windows works fine.
My entire flex sdk folder has execution permission.