This question from Peter:
"I recently was offered and accepted a full-time English Professor positon at ***** University in Seoul. However, I found out yesterday at the university that the maximum amount of time that non-tenured, foreign faculty - such as myself - can be employed there is four years. As a result, I am considering Seoul-area universities in the future that don't have any limits on length for employment and was wondering if you might know of any universities - including yours - that fit such a description."
There are some unis that have this rule, and some that do not (maybe 50/50?). It has to do with the amount of pension money your school would have to pay you in your 5th year and beyond being significantly more than the amount required for the first 4 years. My uni doesn't have the rule and there are plenty of us that have been here for over 5 years. It's just something that you have to ask about at the interview and before accepting a job. It's not like many of the schools will just come out and tell you, because a lot of people, such as yourself would be scared away.
That said, working for 3/4 years at a place is a decent amount of time and it's probably still worth it to take the job, if it's a good one. Being stuck in a rut is never a good thing, so you can just think of it as a mandatory kick in the butt to get yourself moving upwards and forwards in your ESL Teaching career to bigger and better things.