Link a class from another class

i have a monster hitting my character, and when i didn’t had a class in my char i had

if (this.hitTestObject(_root.getChildByName(“personagem”)))

but now it doesn’t work, because i created a class of my character, so i tried

if (this.hitTestObject(_root.personagem))

but it doesn’t work.

How can i connect to the class of the char from the class of the monster?