I am trying to implement a bit of encryption in my Air application while communication with a PHP backend server. For this purpose I am using as3crypto library and I can't read the public key to make the encryption possible. Here is my action script code:

var rsa:RSAKey = PEM.readRSAPublicKey(this.readApplicationFileContents('server.crt')); 

if ( rsa )  
{
    var encodeSource:ByteArray = Hex.toArray(Hex.fromString("Hello World"));  
    var encodeDestination:ByteArray = new ByteArray;  
    var encodeDestination2:ByteArray = new ByteArray;  
    rsa.encrypt(encodeSource, encodeDestination, encodeSource.length)  
    rsa.decrypt(encodeDestination, encodeDestination2, encodeDestination.length);  
    trace(encodeDestination2.toString());  
}  


private function readApplicationFileContents(filePath:String):String  
{   
    var fileObject:File = File.applicationDirectory.resolvePath(filePath);   
    var fileStream:FileStream = new FileStream();   
    fileStream.open(fileObject, FileMode.READ);   
    var fileContents:String = fileStream.readUTFBytes(fileStream.bytesAvailable);   

    return(fileContents);   
} 

readApplicationFileContents function returns the proper certificate contents as a string. But rsa variable always returns null.

It would have been easier if I was able to compile the as3crypto library so I can debug through the source, but I can't get the library to compile and can't find any instructions to do the same. Anyone have a clue what's wrong?

PS. Sorry first time poster and I can't seem to get the syntax highlighting right. Must be Chrome is not working well with the editor.