Check for empty hat, somehow claymore managed this, this should be a workaround pending figuring out how he did it.
#!/bin/bash
svn export --force share/hedgewars/Data ../iphone-hwengine/Data
rm -rf ../iphone-hwengine/Data/Sounds/*
rm -rf ../iphone-hwengine/Data/Music/*
rm -rf ../iphone-hwengine/Data/Locale/hedgewars_*