In an interesting sample of pedophiles he shows that the occurance of molestation is not necessarily an occasional crime certain people commit, but more an intense predation like we see with the psychopath:

"Aben and Osborn (1992) have provided clear evidence that pedophilia is predation. In the examination of pedophilic acts committed by 453 offenders, these authors found that these individuals had molested 67,112 victims, resulting in 106,916 acts of child molestation. Simple arithmetic reveals that these figures yield 148 victims and 236 acts per pedophile. It would be unreasonable to suggest strongly that these acts occured by chance. The sheer numbers suggest strongly that these perpetrators were actively preying on thier intended victims."

Here is a bit more below; 

Psychopathy in the Pedophile By Darwin Dorr

This Chapter presents the thesis that the majority of pedophiles are psychopathic, or manifest to a significant degree the psychological characteristics of psychopathy. Stated conservatively, there appears to be a high rate of co-morbidity between the two forms of behavioral disorder. Asserted more boldly, it is argued that pedophilia may represent a special case, or subcase, of psychopathy. The primary aims of the psychopath and the pedophile are the same: to dominate, to use, and to subjugate another person in service of the grandiose self. The major difference between the two is that in the pedophile, the object of the predation is a child and the overt behavioral manifestation of the pathology is sexual. The thesis of this chapter is that the dynamics of psychopathy are clearly evident in the majority of child molesters. Extrapolation of our knowledge of the psychological dynamics of psychopathy may deepen our understanding of the pedophile, and thus may guide our diagnostic and treatment interventions.

It is notable in large numbers of works on the pedophile that the terms "antisocial personality", "psychopathy", and "psychopath", are never mentioned. It would appear that many authors recognize no link between psychopathy and pedophilia whatsoever. One explanation might be that many workers in the area of pedophilia are in nonclinical fields, such as criminal justice, sociology, or counseling; thus, they are not accustomed to thinking in terms of formal diagnostic categories, or even diagnostic conceptualizations. In my view, this limits their ability to theorize about the pedophilic personality. Clinicians know much about the dynamics of the psychopath, and I am asserting that many of these elements of psychopathy are also present in the pedophile

[here the author goes on to compare the two disorders, and their criteria, to provide a very convincing case that pedophilia is usually a form of psychopathy. He takes about 15 pages to carefully present the facts, and then finishes with the paragraph below:]

My intent in this chapter has been to assert that the behavior and psychodynamics of the pedophile have a psychopathic-like quality. The overt modus operandi is more specialized in the pedophile (i.e., sexual behavior with a minor), but the deeper aim -to assuage one's inner emptiness by dominating or controlling someone weaker and less able to manage the situation- seems strikingly similar to the style of the psychopath….. Although I believe that there is substantial merit to the argument being advanced, I am aware that it is not without flaws. Since we are dealing with two spectrum disorders, identical isomorphic overlay is unlikely. However, I have never seen a pedophile in my forensic practice who did not exhibit some psychopathic tendencies. Furthermore, I have never examined a pedophile who demonstrated tight reality testing, mature defenses, sound judgement, adaptive regression, efficient thought processes, or any other signs of mature ego functions. Instead, each one demonstrated marked character pathology of the kind seen in psychopathy. I believe that much can be learned about pedophilia by conceptualizing it as being closely related to, or a special case of, psychopathy. As we further our knowledge of this unfortunate disorder, we will improve our chances for successful treatment and improve the future for our children.

[From 'Psychopathy' - by Theodore Millon]

Courtesy "bewildered"
"As I have said before, the primary focus of my work is with sex offenders, a great many of whom are pedophiles.  Many, although not all, have a diagnosis of anti-social personality disorder (sociopath/psychopath).  Of those who do not have this diagnosis (799.99 diagnosis deferred on Axis I or Axis II), there is often the note that the therapist/clinician/etc.  needs to take further steps to rule out the possibility of other personality disorders, often with narcissistic, borderline, paranoid, or anti-social tendencies.  These people usually don't really understand the impact of their behavior (that is if they even admit to the behavior--many never admit it or, if they do, admit only to an accidental touch or a misunderstanding of motive, etc.).  A major focus of the counseling/education they receive is to teach them to not re-offend, even if the only reason they don't reoffend is to avoid punishment.  Also, we try to teach empathy for the victim and an understanding of appropriate behavior in life and particularly in relationships, sexual and otherwise.  Also, we use aversion therapy (association of unpleasant smell--ammonia--with inappropriate thoughts and/or impulses) as well as other, more gross (sexually explicit) methods to attempt to reduce the frequency and desirability of their thoughts, fantasies, etc.  Unfortunately, these methods depend largely on the client wanting to change and being willing to voluntarily do what is necessary to stop their behaviors.  Most just don't want to go back to jail and try to behave only to prevent another jail term.  A true pedophile is usually not curable--like psychopaths. "