Losing my XP when traveling from The End to the world

[Qwalk]

I've set up a neat Enderman farm in The End, so I can gather XP and loot fast.

But the only issue is that I don't get to bring my XP with me when I return to the normal world.

For example when I enter The End I am lvl 6, I farm some XP and am lvl 30 when I want to leave The End, when I return through the generated portal I am lvl 6 again. I am getting all my loots but not the XP. Really annoying!

Also when I killed the dragon mob, I got like 70 levels of XP, but when I returned through the generated portal and went through credits, I lost them all.

What can I do about it?

PS: I don't know if it could be something to do with my other issue, which I posted here:

http://forums.technicpack.net/threads/gamemode-resets-to-creative-in-new-dimensions.50699/