Minecraft CrackPack gravitational force keeps killing me?

So, while playing on my Minecraft CrackPack server (otherwise commonly known as Feed the Beast), I came across this sort of gravitational pull that sucked me towards it and then threw me up into the air and killed me. Even with my jet pack, it wouldn't let me fly away. Is there any way to get my stuff back without dying or to kill it or what? Please Help! Every time I get near it it just throws me into the air and forces me to crash and die!