5.0,1 beta: "GetTimeZoneInformationForYear" not found

After upgrading to 5.0,1 beta on Windows XP SP3, winscp.exe shows this (german) error message on startup and then terminates:

Der Prozedureinsprungpunkt "GetTimeZoneInformationForYear" wurde in der DLL "KERNEL32.DLL" nicht gefunden.

Translates as

procedure entry point "GetTimeZoneInformationForYear" was not found in "KERNEL32.DLL"

See this thread.