Found on a mailing list:

Eye halve a spelling checker
It came with my pea sea
It plainly marks four my revue
Miss steaks eye kin knot sea.

Eye striks a key and type a word
And weight four it two say
Weather eye am wrong oar write
It shows me a strait a weigh.

As soon as a mist ache is maid
It nose bee fore two long
And eye can put the error rite
Its rare lea ever wrong.

Eye have run this poem threw it
I am shore your pleased two no
Its letter perfect awl the weigh
My checker tolled me sew.