lateral player falling

[Xabache]

Am trying to plug a leak in my San Andreas Prison: high fences, no escape, certain death, but some players join and before the download finishes climb ten feet up a small building then run toward the edge and float 500 feet or more at that same altitude over the fence. They float through the air in the falling anim, not the halfway though my jump anim of low gravity but the oh sh*t, arms and legs flailing anim of a long vertical fall, but this is never vertical, And they move laterally at the same altitude continually and do not fall... all before the download is even finished. What is this?