When spell check can't help

I see this malapropism way more often than I should, but it still cracks me up every time. This was a Contractor's question:

Are YKK and Kawneer acceptable window manufacturers under specification section 08520-2.1 as was listed under WEST CHILLER PLANT?

And the architect's response:

Yes. As long as these (or any) manufacturers can meet all of the requirements of the specifications. (Pay particular attention to mutton size requirements).

Just to clear the record:

mut·ton : the flesh of a mature sheep used for food
mun·tin : a strip separating panes of glass in a sash