@ jncraig: thanks for your reply. I looked into the new skin object, but it's a littje too complicated for my novice level .... at least for now.
For the time being I'm using just a simple shortcut:
{a class="SkinObject" href='<%= DotNetNuke.Common.Globals.NavigateUrl%>&language=en-EN'}english{/a}
(replace { and } with < and > )