Where parties have established a course of dealing governing the mechanics of performance, that course of dealing qualifies the manner in which obligations under the agreement are to be discharged, without negating the existence of the agreement itself. A course of dealing goes to the mode of performance, not to the existence of the contractual undertaking. C. Strict Adherence to Pleadings 26. The Federal Court in RHB Bank Bhd v Kwan Chew Holdings Sdn Bhd [2010] 2 MLJ 260 reaffirmed that parties are bound by their pleadings, and that a court has no jurisdiction to award a remedy in respect of a cause of action that has not been pleaded. A material fact that first surfaces in oral testimony, without having been pleaded, does not thereby become part of a party's case. D. Admissibility of Computer-Generated Documents 27. Section 90A of the Evidence Act 1950 provides, in material part, as follows: "In any proceeding a statement contained in a document produced by a computer shall be admissible as evidence of any fact stated therein of which direct oral evidence would be admissible, if it is shown that the conditions in subsection (2) are satisfied in relation to the statement and computer in question." Subsection (2) stipulates that the conditions are satisfied if, among other things, the computer was used regularly to store or process information for activities regularly carried on over the relevant period, and the information was supplied to the computer in the ordinary course of those activities. Section 90A(3) provides that these conditions may be established by a certificate signed by a responsible officer. The Court of Appeal in Lim Peng Hock & Anor v Chuah Peng San & Anor [2017] 5 CLJ 361 affirmed that compliance with Section 90A is a mandatory prerequisite for the admissibility of computer-generated documents as substantive evidence. E. Hearsay and the Maker of Documents 28. A document tendered to prove the truth of the facts asserted therein is hearsay if the maker is not called to testify. In Live Capital Sdn Bhd v Pioneer Conglomerate Sdn Bhd [2008] 6 MLJ 577, the Federal Court affirmed that where a party seeks to admit a document as substantive evidence, the maker must ordinarily be called so that the opposing party may cross-examine as to its contents and authenticity. F. Mitigation of Loss and the Duty to Notify 29. An aggrieved party is under a duty to take all reasonable steps to mitigate loss consequent upon a breach. Where the mitigation measure involves an on-sale to a third party at a differential price, commercial fairness requires that the defaulting party be put on notice before such a measure is executed, so that the defaulting party has an opportunity to respond. In The "Asia Star" [2010] 2 SLR 291, the Singapore Court of Appeal held that a seller proposing to on-sell goods to a third party at a loss ought first to notify the buyer. The Supreme Court applied similar reasoning in Eikobina (M) Sdn Bhd v Mensa Mercantile (Far East) Sdn Bhd [1993] 3 MLJ 369. G. Adverse Inference for Failure to Call a Witness 30. Section 114(g) of the Evidence Act 1950 provides that the court may presume "that evidence which could be and is not produced would, if produced, be unfavourable to the person who withholds it". In Takako Sakao v Ng Pek Yuen & Anor [2009] 6 MLJ 751, the Federal Court affirmed that an adverse inference is warranted where a party fails to call a witness who is within that party's knowledge and control and whose evidence would be material to the issues in dispute. H. Unpleaded Set-Off 31. A set-off, being a substantive defence reducing or extinguishing the plaintiff's claim, must be specifically pleaded. A party may not advance at trial a set-off that was not pleaded, as to do so deprives the opposing party of the opportunity to traverse and meet that case: RHB Bank Bhd v Kwan Chew Holdings Sdn Bhd. VI. ANALYSIS AND FINDINGS Issue 1: Formation of Contracts 32. The Defendant's primary position is that no binding contracts existed at all, and that Alice's emails were merely preliminary discussions without legal force. This Court rejects that position.