Walls and Ceilings - sheetrock "separation"

We have an old balloon frame house that used to have plaster, which we beat out and had sheetrocked (approx 1998). From the beginning the sheetrock got cracks where the walls meet and where the walls meet the ceiling. This is throughout the house. It seems this specific type of cracking pattern would be indicative of something, but what? The house is pier and beam, and there may be some foundation issues, but this is not the type of settling/swelling cracking frequently seen in this area. Is it a framing issue (we wonder if the plaster was holding the house together before--only half kidding!). If you have seen this type of cracking before please let us know what caused it and how it was fixed. Many thanks.

Just off the top of my head, it sounds like you did not put in sheetrock corners. those types of cracks are usual when corners were not used.