Error in CKEDITOR.replace () in standard package

When I try to call the CkEditor replace method with the standard package (plus the German language pack), I get the following error in JavaScript:

TypeError: d - undefined

... + e})} if (! A.blockless) {var q = a.lang.bidi; F ("BidiLtr", d.ltr, "bidiltr", m ("l"), 10) ...

If I use the full package (also with the German language pack) everything works fine. Any ideas what the problem might be? I just call the replace method from the example in both cases:

CKEDITOR.replace( 'editor1' );