I highly recommend these resources....
http://www.askdrsears.com/html/7/T070100.asp
"Distressed Babies Need to be Held"
http://www.mothering.com/crying-comfort-distressed-babies...
"Babywise Advice Linked to Dehydration, Failure to Thrive"
http://www.ezzo.info/Aney/aneyaap.htm
As the mother of a former high-need child, I also highly recommend a lot of holding and rocking and nursing. Your baby had non-stop 24/7 physical contact with you for the only life that he had known until birth (in the uterus). For him, to try to sleep on a hard, non-flesh, surface that doesn't move or make sounds is a very strange experience indeed, especially as early as 3-4 months of age. Ashley Montagu, an anthropologist, in his book "Touching" says that human babies aren't actually done with their gestation until 9 mo. after their birth. So he says that ideally they should be held continually for the first 9 months of their post-birth life.
http://www.amazon.com/Touching-Human-Significance-Ashley-...
I also highly recommend using a lambskin specifically designed for baby-use (they are real lambskin but can be laundered as needed).
http://www.sheepskintown.com/baby-sheepskin-short-wool-p-...
http://www.kiwi-sheepskins.com/detail.asp?product_id=BA001
http://www.sheepskinfurs.com/27-baby-lambskins.html
You might also find some help by taking a look at this book, which is probably in your local public library (or at least available through inter-library loan)...
http://www.amazon.com/Family-Bed-Concept-Child-Rearing/dp...
Cooperation with what a baby needs (rather than expending a lot of energy in fighting those needs) often makes everybody happier and healthier.
I do not recommend letting him cry it out. I believe that that kind of treatment causes a deep grief in babies, which can leave internal emotional scars for the rest of their lives (unless they get treatment for it).
I also disagree with the belief that if you don't let him cry it out, then for many years you will have a child who will not transition to a more grown up style of sleeping. The people who practice attachment parenting, in which the parents respect the needs and natural growth patterns of their children, have found that the opposite is true. Those children who frequently have their requests for holding and nursing and sleep needs denied are the ones who are most commonly the fearful and tense and clingy ones. Those children who are constantly respected and made to feel heard, and who get the amount of holding and nursing and physical contact that they ask for, are the ones who are peaceful and self-confident and more likely to move on to separations from their mothers at a normal pace.
I often think that people who suggest the cry-it-out method might feel differently about the issue if they would think about how they themselves would feel if they were asking and asking and asking for love and holding and attention and comfort and reassurance and a listening ear, and getting ignored by their loved ones (husbands, family, friends, pastors, or whoever their support network is), and then sobbing and sobbing and sobbing for that, and still getting ignored by their loved ones.
When a baby starts waking up more times in a night than s/he had been for awhile, it simply means that s/he is going through some kind of change or development stage in which s/he NEEDS more holding or nursing or something, NOT that they are somehow regressing in a negative sense. When we ignore those needs, we are not being sensitive to or caring for our babies' legitimate growth processes and changing needs. The baby has no way of reading the mind and knowing of the good intentions of her/his mother. The baby can only feel ignored and unheard and abandoned and alone and very, very, very profoundly sad and grief-stricken.
I would also like to add that if you start giving him a pacifier, you may find that your milk supply may start decreasing.
Best wishes,
J.