[2] The respondent, who was the second defendant in the action, was sued under the letter of guarantee dated 3 October 1984 (the said guarantee following the default of the principal borrowers, whereby, as a director, he guaranteed to pay the appellant bank all sums due and owing under a revolving bankers acceptance facility granted by the bank to the principal borrowers. His liability was, however, limited to RM2.0 million. Being an "on demand" guarantee, the appellant's solicitors sent him a notice dated 4 March 1988 by AR registered post to his last known address, demanding payment of the amount owing. On 19 M