My tongue in cheek answer would be the column is already sorted.

Nice try :)
However, the next question is, have you attached a LvFullRow object as the data item for every item in the list-view?  If not, the sort won't work.

If you attach a LvFullRow object as the data item for some, but not all, of the list-view items, the outcome is non-deterministic.

Hmm, no I haven't. I believe I must have misunderstood the documentation in that case. I've somehow read it that only if something but a row item should be used for internal sorting then this requirement comes into play. Re-reading it I'm unsure how I came to that conclusion. I'll try again.