And new Villa boss Houllier is backing the often maligned Heskey, who stepped down in the aftermath of the World Cup, to play a major role for the midlands club.
Heskey impressed as a substitute during the midweek Carling Cup win over Blackburn, scoring once and setting up two goals for Ashley Young in a 3-1 success.
He was often used as a substitute under Martin O'Neill but could come into contention to start Sunday's derby encounter at Wolves.
Houllier said: "He decided to stop his international career so now it means he can repeat games for us.
"The whole England team suffered (received criticism) for what happened in South Africa.
"But, if you remember the game against Germany, and I was at it, if the goal from Lampard had been allowed it would have been 2-2 at half-time.
"Sometimes things go your way, sometimes they don't, but whatever you say about Emile he is a good man and a good player.
"I read a few things about what he said when he retired and it's very sensible what he said, that his time has gone now, he's 32-33, there are some young players coming through.
"Emile will be 100 per cent Villa and as the manager I am happy."
Houllier signed Heskey when Liverpool boss from Leicester a decade ago in an £11 million deal and has no doubt he can still be a major force.
He said: "All strikers need confidence. They need to feel they have the backing of the manager, club and the fans.
"Emile probably needs that more than the others. I saw him play on September 4 in Jamie Carragher's testimonial.
"Garry McAllister (Villa assistant-manager) was also involved in that game and he said Emile has still got something about him.
"Trust me, I think he will do well for us."
Houllier insisted strengthening the striking department was not a first priority on his agenda.
He said: "We have got three strikers in Agbonlahor, Carew and Emile. I don't think we have to sign another.
"If we have to sign a player now, it won't be in that area."
Houllier is confident his side have the physical presence to match Wolves even if his side are not the biggest in terms of physical stature.
He said: "I've seen them on the video. They are a good side.
"They seem to play, will be good opposition, physical as always with the English game. It will be a very competitive game.
"The Premier League has got more physical.
"It is not about a matter of size. You need size in some positions but is also a matter of commitment and physical commitment. We have that."
Agbonlahor is winning his fitness battle after resuming training. He suffered two tight calves against Blackburn and was substituted during the first half.
Midfielder Stephen Ireland is also on course to play after resuming training following a dead leg.
But central defender Richard Dunne is again sidelined with a knee problem although Houllier is optimistic he can return against Tottenham next weekend.