This can be made a day ahead, and it freezes well too.

Crust; In bowl, combine wafers and butter. Press into 13 x 9 inch glass b aking dish. Refrigerate.

Filling; In saucepan, cook gelatin, salt, coffee and milk, stirring consta ntly, over medium heat until hot and coffee is dissolved. Reduce heat. Sti r a little coffee mixture into egg yolks, then pour egg mixture back into s aucepan. Cook, stirring frequently, until mixture thickens slightly, 4 - 5 minutes. Remove from heat and add liqueur. Using electric mixer or food pro cessor, blend cream cheese and 1/4 cup of the sugar until smooth. Slowly bl end coffee mixture into cream cheese. Chill, stirring occasionally, until c onsistency of raw egg whites, about 1 - 1-1/2 hours. Meanwhile, melt chocolate in double boiler over hot water. Let cool. Beat egg whites until soft peaks form. Gradually add remaing sugar and beat unti l stiff peaks form. Gently fold egg whites into coffee mixture. Transfer 1-1/2 cups of coffee mixture to small bowl and fold in chocolate. Using large spoon, alternately spoon two mixtures over chocolate crust. Use knife to swirl chocolate through