Combine graham cracker crumbs, 7 tablespoons melted butter, and 1/4 cup sugar in a large bowl.

Press the mixture into an ungreased 13x9 inch dish.

Freeze the crust until firm.

In a separate large bowl, combine softened vanilla ice cream and lime sherbet.

Pour the ice cream mixture over the frozen crust.

Freeze until firm.

In a heavy saucepan, combine eggs and the remaining sugar.

Stir in the lemon juice and the remaining melted butter.

Cook and stir over medium heat until the mixture reaches 160°F and coats the back of a metal spoon.

Cover and refrigerate the lemon sauce until cool.

Spread the cooled lemon sauce over the frozen ice cream mixture.

Cover and freeze for at least 3 hours, or preferably overnight.

May be frozen for up to 2 months.

Just before serving, remove the dessert from the freezer and cut into squares.