Mailing labels PDF national characters broken

See http://forum.civicrm.org/index.php/topic,20300.0.html

The rewrite of Mailing Labels functionality in CRM-7981 drops the TCPDF default Deja Vu font in favor of Helvetica, Courier and Times. Unfortunately these fonts don't support special national characters (e.g. ě č ř) and mailing labels where these are used are broken (displaying '?' in place of the special character).

Partial fix is to register the special-characters-capable TCPDF default Deja Vu font in CRM\Utils\PDF\Label.pdf at line 189 and then instruct users to manually update their labels in case they need unicode support.
Full fix is to register dejavusans as well as update all the default labels to use it again, and make Helvetica, Courier and Times only an option (ideally with a disclaimer like 'ASCII' in the displayed font name).

Thanks!