When plack is not running, 500 errors will show the error message of the perl file where the error occurred, as well as a contact email address, something like this: 500 Internal Server Error Use of uninitialized value within @itemnumber in string ne at /usr/share/koha/intranet/cgi-bin/reserve/modrequest.pl line 70. To report a broken link or any other issue, please contact the Koha Administrator. (I think the text is actually from koha-tmpl/intranet-tmpl/prog/en/modules/errors/errorpage.tt) Under plack, all we see is Internal Server Error This means that a) Errors are less likely to be reported to the server administrator because there's no mailto. b) We can't immediately see the error message when the error is reported.
Would really love to see a fix for this.
*** This bug has been marked as a duplicate of bug 26048 ***