A genuine question (as in I don't know the answer) - but who knows what the origin of Jebel Ali is?
Jebel = mountain, Ali = name of a person - so it means 'Moutain Ali' or 'Ali's mountain'.
However, there isn't a mountain there as far as I can tell.
Google, for once, failed me - but it was interesting to see the entry under Wikipedia for Jebel Ali, apparently it's the most visited port by the US navy outside of US, and it says that all sailors who go abroad have been to Jebel Ali. There are permanent 'liberty' houses on shore referred to as the sand box or somethiing similar.... but no indication where the name comes from.
Cheers,
Shafique