Math.ceil often gives wrong result on device

[natevw]

I have a calculation like this:

var res = Math.ceil((92 + 0) / 64);
console.log(res);
console.log(Math.ceil(0.9), Math.ceil(1.4), Math.ceil(2.5), Math.ceil(3.9));

And it's right under POSIX colony but wrong on device:

postel:runtime natevw$ node t_ceil.js 
2
1 2 3 4
postel:runtime natevw$ colony t_ceil.js 
2
1 2 3 4
postel:runtime natevw$ tessel run -s t_ceil.js 
TESSEL! Connected to TM-00-02-f0009a30-005d4757-6c8045c2.
WARN Warning. Deploying just this file.
INFO Bundling directory /Users/natevw/Desktop/Clients/Technical_Machine/runtime
INFO Deploying bundle (3.50 KB)...
INFO Running script...
1
1 2 2 4

[natevw]

What's intriguing is that this simply calls Lua's math.ceil — bug in LuaJIT for this arch?