"D[efender] generates a damage value and A[ttacker] generates a protection value. If the damage value is greter than the protection value, A[ttacker] takes one hit point of damage."
Judging from this, if this is accurate, I'd quess that Sleep Wines and Wails etc. couldn't give that 1 hp of damage. They could, however, cause the attacker to abort its attack, as the morale check doesn't ask for weapon's damage.
It'd be better to test it, however. This is all theory, and as I read in a sig yesterday (BTW, Wick, welcome back!
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):
"In theory, practice and theory are very similar. In practice, they are often quite different."