can a step parent adoption be reversed

here is the story many years ago(17) i slept with a woman she had a child but didnt contact me about the child for many years, within that time she married a man they lived in texas he adopted the child in 2002 amended the BC on the application they stated that there was no known father. they had 2 kids together and then later divorced, he has custody of their 2 natural children she has custody of the child in question. now in 2008 she is requesting paternity from me and child support here in ny where she and the child are living. at the time of the adoption i would not have challenged the adoption and i had no contact with the child nor did i pay child support at any time. i have no intent on challenging the adoption now........can they or a state agency reverse the adoption now?