Sometimes, I make my players make a ranged touch attack against the ground for this sort of thing. I rule that Jump has a range increment of double the character's ranks. If the object they are jumping at is moving, it has an effective Dex score of (move / 10).
Example: Jo has 15 ranks in jump, the Ring of Jumping, 7 ranks in Tumble, skill focus (JUMP), the Acrobatic feat, and Str 18, for a total modifier of +55 to jump skill. His range increment while jumping is 15'. He leaps at a moving platform 35 feet away. He rolls a 7, for a total of 62, more than enough to cover the distance. He then makes a ranged touch attack (+15 base, +2 dex, -2 increments, +15 total) against AC 8 (the block is Large, has an effectiv Dex of 8 from movement). Jo rolls a 7, or a total of 22, more than enough to beat AC8, so lands on the block.
Just one schleps take on the issue,
-Jeph