Help Elderberry wine going mental!

[salmac]

Ive just made some elderberry wine and added the yeast last night, its now absolutely going mental, its managed to expand so much its pushed fluid out of the airlock, which Ive now taken off but its still going like crazy. There was a fair amount of airspace in the mash tun to start off with.
Err any suggestions? ie Take out fluid, let it be etc

Thanks

Sal