Williamsburg, Va.--The American Business Press at its spring meeting today urged all its members to contact their congressmen about the upcoming May 18 vote on postal legislation. Rae Evans, ABP's Washington representative, told attendees that bill H.R. 22, if passed, could potentially raise their postal costs 20%. Every member received a copy of a form letter that they could mail to members of the subcommittee responsible for the bill. The letter states that ``large bulk mailers would likely receive increased discounts for their mail. Such unequal treatment is fundamentally wrong.''