Would it be possible to get a clay bucket API? I would like to add support for Sludge, Sewage, and other liquids from MineFactory Reloaded. Alternatively, the support could be native, although I'm not sure how I'd contribute this to the source.

Would you consider adding support for Ex Nihilo witch water and clay buckets?

I have made a small mod which adds support for various fluids, mainly forestry and MFR. It needs a custom build of Iguana Tweaks though, due to a bug In the clay bucket code. I could add Ex Nihilo and put it up somewhere if you're interested?

That would be great thanks.

Is it a general fix? If it's safe and you PR it you can use a jenkins build for it.

Thank you TW looks great

Here's the mod which adds support for more liquids. Built against forge 1558. https://github.com/TinkerWorX/IguanaTweaksMoBuckets/tree/master
It requires the latest commits to IgTweaks, which you'll either have to build yourself or ask boni nicely about.

Actually, we have a Jenkins for that: https://dvs1.progwml6.com/jenkins/job/IguanaTConTweaks-1.7.10/lastSuccessfulBuild/artifact/build/libs/IguanaTinkerTweaks-1.7.10-2.1.5.149.jar

The claybuckets are hardcoded and completely separate from everything else. Clay buckets for other materials could be added by any mod - they are required to be separate items.
You can find everything in the claybucket package.

Alright, so if I'm understanding this right, I just make a FillBucketEvent handler, check for the fired clay bucket and then implement the behavior of a bucket.