Are you sure you updated the right file. The skin files used by the site are at /Data/Sites/[SiteID]/skins/[SkinName]
where SiteID isusually 1 for a single site installation and SkinName is the name as you see it in Site Settings.
The skins under /Data/skins are just a catalog where skins come from when creating a new site.
Hope it helps,
Joe