Well, before anyone jumps to any conclusions, socionics IS different from MBTI. The last j/p doesn't always stand for the same thing.
So, if you don't do some lovely conversions, then it won't come out right!
I've done some stuff with socionics, and from what I've heard, a way to kind of even it out so it's a little more accurate is to change the last j/p FOR INTROVERTS.
In other words, I'm INFJ in MBTI, but for socionics I'm INFp. And you do that for all introverts, from my experience. But it stays the same for extroverts: ENFJ is still ENFj.
So, to convert it:
ENTp - ISFj
ESFj - INTp
ENFj - ISTp
ESTp - INFj
ESFp - INTj
ENTj - ISFp
ESTj - INFp
ENFp - ISTj
There. That's better.
Although I still wouldn't recommend going with this 100%; I'd use it as sort of a suggestion towards a type, if anything. Especially because this isn't really an exact method; it's just a tad bit more accurate, and I trust it a wee bit more myself because I've used it and could see some correlation with RL.