Not sure if this was fixed yet, but it is broken in my version
#$Id: genbank2gff3.PLS,v 1.5 2005/01/17 19:48:57 cjm Exp $;
Line 248
$fa_outfile =~ s/gff/fa/;
if the string "gff" is in your --outfile, this creates problems
It should be changed to
$fa_outfile =~ s/gff$/fa/;
-Michael Cipriano