Beat'em Up game

[Bruto_JPO]

Hi I'm from Brazil and I'm developing a Beat'em Up game for my conclusion work in universisty. I'm using a game api in this site trunk - sporksoft - Project Hosting on Google Code

This game api is exactly the same as the jme.

I'm having a problem, each time I use a game api method I have an null error and my app stop.

 //Method that adjusts Axel's sprite
        public void adjustAxel( Sprite s, double mx, double my ){
            try{
                mPositionX = (int) mX;
                mPositionY = (int) mY;
 
                mManager.append( mAxelSprite );
                mAxelSprite.defineReferencePixel( mAxelWidth / 2, 0 );
                mAxelSprite.setRefPixelPosition ( mPositionX, mPositionY);
                mAxelSprite.setFrameSequence( mFrameSequence );
              }catch( Exception e ){
                        Log.e( CATEGORIA, "Error 2: " + e.getMessage() );
                   }
        }

I don't have an idea how to fix it, and in my country are very few people that develop in android platform so here I'm to search for help.

Greetings
John Peter