Error in PurePDF class

Hello all. I got a problem when I trying use the **PuerPDF class**. I downloaded the package, dizip and set the libary path to path where is the swc files. I created a new file based on HelloWorld example with external class with the same code of the example: [URL=“http://code.google.com/p/purepdf/source/browse/examples/src/HelloWorld.as”]http://code.google.com/p/purepdf/sou…/HelloWorld.as

When I run, I got this errors. How can I solve this?

1067: Implicit coercion of a value of type flash.utils:ByteArray to an unrelated type org.purepdf.pdf:Lock.