1public void SetCulture(string siteUrl)
2        {
3            try
4            {
5                CultureAndRegionInfoBuilder.Unregister("pl-PL");
6            }
7            catch { }
8
9            CultureAndRegionInfoBuilder carib = new CultureAndRegionInfoBuilder("pl-PL", CultureAndRegionModifiers.Replacement);
10            carib.LoadDataFromCultureInfo(new CultureInfo("lt-LT"));
11            carib.LoadDataFromRegionInfo(new RegionInfo("lt"));
12            carib.GregorianDateTimeFormat.ShortDatePattern = "yyyy-MM-dd";
13            carib.Register();
14
15            CultureInfo ci = new CultureInfo("pl-PL");
16
17            SPSecurity.RunWithElevatedPrivileges(delegate()
18            {
19                using (SPSite site = new SPSite(siteUrl))
20                {
21                    using (SPWeb web = site.RootWeb)
22                    {
23                        site.AllowUnsafeUpdates = true;
24                        web.AllowUnsafeUpdates = true;
25
26                        web.Locale = ci;
27                        web.Update();
28                    }
29                }
30            });
31        }