Bug: sheep farm ships to dairy?

[Fraoch]

pak128 2.2.0 with a recent nightly Simutrans 112.1.1 on Ubuntu Linux 12.10 64-bit.

Both a sheep farm and a dairy indicate they can ship to each other, but what?  The only items that the sheep farm produces are meat and wool - the dairy only accepts milk and glass.  I constructed a track between the two and neither a cooled goods train nor a piece goods train would load at the sheep farm.

This seems like a bug?