[support] problem with fckedito on multisite

I have created a new site in a multisite installation. On all previous installations fckeditor works without any problem, but on the last one it doesn't. Firebug isn't working right now, but I have found on firefox console the next error:

Error: missing ] after element list Fitxer font: http://www.escoltesiguies.cat/conferencia_corea/node/add/page Línia: 166, columna: 194 Codi font: oFCK_1.Config['ToolbarSets["Default"]'] = [oFCK_1.Config['EditorAreaCSS'] = "/conferencia_corea/themes/internacional_corea/style.css,/conferencia_corea/sites/all/modules/fckeditor/fckeditor.css";

This errors isn't happening in other sites. I tried changing the theme but it continues without working.

Any hint?

thanks