Comment # 19 on bug 937020 from Dr. Werner Fink

(In reply to Martin Jakl from comment #18)

There are three entries for pdfcsplain in /etc/texmf/web2c/fmtutil.cnf and due
to an update there might be a /etc/texmf/web2c/fmtutil.cnf.rpmnew which is that
at update an existing fmtutil.cnf will not replaced but the new placed as
fmtutil.cnf.rpmnew.  This is why it had work here.

I'll see if this remains in TeXLive 2015 if I find the time to handle this.