NEW YORK, May 15 -- Crude oil futures dipped slightly on Thursday after Iran's state media said about 30 vessels had crossed the Strait of Hormuz in recent hours, while the semi-official Fars news agency cited a source saying Iran had begun allowing transit for some Chinese vessels. Brent crude oil futures were down 73 cents, or 0.7%, at $104.90 a barrel at 11:21 am ET (8:51 pm IST), easing from an earlier high of $107.13. U.S. West Texas Intermediate futures were down 20 cents, or 0.2%, at $100.82. Both contracts fell on Wednesday as investors worried about possible U.S. interest rate hikes as higher fuel prices spur inflationary pressures. P11...