CIVIL PROCEDURE — Res Judicata — Conditions for Estoppel Per Rem Judicatam

"It is judicially recognised by a long line of cases that for a plea of estoppel per rem judicatam to succeed, the party relying on it must establish the following requirements or pre-conditions, namely: (1) That the parties or their privies are the same in both the previous and present proceedings. (2) That the claim or issue in dispute in both actions is the same; (3) That the res or the subject-matter of the litigation in the two cases is the same; (4) That the decision relied upon to support the plea of estoppel per rem judicatam must be valid, subsisting and final; and (5) That the court that gave the previous judgment relied on to sustain the plea must be a court of competent jurisdiction."