my son will be 4 soon he likes to use the pacifier whenever sleepy or tired. even when he is watching his favorite cartoons...he sits back and asks for it (like guys smoke at time of relaxation ;-)) should i be worried that he may not leave it....or he will grow out of it ? by the way, he does not ask for it when playing with kids or outside.

I think you need not be too worried. He does not seemed to be overly reliant or attached to his pacifier since he doesn't ask for it when he is outside. Sounds like he just enjoys suckling on it (while doing mundane things that's not too engaging). If you are really worried and would like to try weaning him off, simply have a talk with him. Tell him that he is going to be a big boy now and needs to say goodbye to his pacifiers. Have a "ceremony" to put away all his pacifiers to help with the transition (just letting him put everything in a box would do and keep the box away). He sounds like he would be ready for this and should be able to move on easily.