I had the same issue with another package (gnokii I think). I removed the partially downloaded file, changed mirrors and then the updates went through.
See if that works for you.
Thanks Santhosh Joseph
On Tue, Sep 29, 2009 at 9:43 PM, Nigel Henry firstname.lastname@example.org wrote:
I had problems with ocaml yesterday. After the machine locked up during the updates, I did a hard reset, and ran pacman -Su again. It continued downloading ocaml, but when all the updates were downloaded, it failed to install them, claiming that ocaml was corrupted. I removed the corrupted ocaml as requested, and as I'm on dialup and didn't want to download 38MB of ocaml again last night, I temporarily added an IgnorePkg line for it.