I hate to disagree, on such an old forum post, but so many people misclassify themselves. The tests for MBTI are terrible, and people often read the cheesy bios which are supposed to be derived from the function stacks! As ENTP I have a similar function stack to an INFJ. We both should have Fe! (as well as the abstract Ti thinking) Some of you are describing qualities of ENFPs, with Fi (less aware of how others feel, less (at first) outwardly sympathetic). While this Fe may not be as high on the stack as an INFJ, it should be a clear undertone in any well developed and healthy ENTP (maybe not as a teenager, but definitely in late college and beyond). Some of you so-called INFJs who are so very critical, make me wonder if your not INTJs or something else. Not that you can't be critical, but in my experience true INFJs (which are so rare, yet so frequent online oddly) see people with a lot of insightful poetry, as though human beings are works of art.
And as ENTP I adore INFJs, we work very well together. We have similar functions, similar values, and humor. In college a girl INFJ told me that she wished she were as brilliant as I, and I being a healthy and realistic ENTP told her that while she may not have read as many books on the subject (she being two years younger in our study), she was equally intelligent and also gifted in ways I was not.
Now maybe we are talking about unhealthy ENTPs or ENFJs/ENFPs (most likely to be typed as ENTP) then you may have a point for compulsive lying and over argumentative behaviors (ENTPs like to argue, but once again Fe shows us when people are frustrated and we know when we go too far). You should know when you meet an ENTP, it'll feel right, possibly weird, or so it does for me meeting an INFJ. They may push you and it can be scary, but only because they like you. Their extraverted intuition should be compelling for you though, as Ni is for me. ENTPs will rapidly fire off analogies that I find INFJs enjoy. AKA the conversations should be quite enjoyable and deep. But they usually always express compassion when you show them that you were hurt (I always do). If they don't, they got serious baggage, or you can bet they are not an ENTP. ENTPs are rationalists, but they are the most sentimental of the rationalists.