From @tamias

(I report this with perlbug for 5.004_04, but I have verified it with
5.005_02)

The names of four of the special variables are output as the control
characters in error messages, rather than in the readable form '^X'.

% perl -e 'my $^I'
Can't use global $ in "my" at -e line 1.
% perl -e 'my $^J'
Can't use global $
in "my" at -e line 1.
% perl -e 'my $^M'
in "my" at -e line 1.
% perl -e 'my $^L'
Can't use global $
  in "my" at -e line 1.
 
All the other control character variables are output with the name as '^X'
instead of the actual control character.

Site configuration information for perl 5.00404​:

Configured by sting at Fri Jan 9 23​:03​:03 EST 1998.

Summary of my perl5 (5.0 patchlevel 4 subversion 4) configuration​:
  Platform​:
  osname=irix, osvers=6.3, archname=IP32-irix
  uname='irix linguist 6.3 12161207 ip32 '
  hint=recommended, useposix=true, d_sigaction=define
  bincompat3=y useperlio=undef d_sfio=undef
  Compiler​:
  cc='cc -n32', optimize='-O3', gccversion=
  cppflags='-D_BSD_TYPES -D_BSD_TIME -OPT​:Olimit=0 -I/usr/local/include -DLANGUAGE_C'
  ccflags ='-D_BSD_TYPES -D_BSD_TIME -woff 1009,1110,1184 -OPT​:Olimit=0 -I/usr/local/include -DLANGUAGE_C'
  stdchar='unsigned char', d_stdstdio=define, usevfork=false
  voidflags=15, castflags=0, d_casti32=define, d_castneg=define
  intsize=4, alignbytes=8, usemymalloc=y, prototype=define
  Linker and Libraries​:
  ld='ld', ldflags =' -L/usr/local/lib -L/usr/lib32 -L/lib32'
  libpth=/usr/local/lib /usr/lib32 /lib32 /lib /usr/lib
  libs=-lgdbm -lm -lc
  libc=/usr/lib32/libc.so, so=so
  useshrplib=false, libperl=libperl.a
  Dynamic Linking​:
  dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags=' '
  cccdlflags=' ', lddlflags='-n32 -shared -L/usr/local/lib -L/usr/lib32 -L/lib32'

Locally applied patches​:
 

@​INC for perl 5.00404​:
  /usr/linguist/lib/perl5/IP32-irix/5.00404
  /usr/linguist/lib/perl5
  /usr/linguist/lib/perl5/site_perl/IP32-irix
  /usr/linguist/lib/perl5/site_perl
  .

Environment for perl 5.00404​:
  HOME=/usr/people/rjk
  LANG=C
  LD_LIBRARY_PATH (unset)
  LOGDIR (unset)
  PATH=/sbin​:/usr/people/rjk/scripts​:/usr/people/rjk/bin​:/usr/linguist/bin​:/usr/sbin​:/usr/bsd​:/usr/bin​:/usr/bin/X11​:/usr/local/bin​:/usr/etc​:.
  PERL_BADLANG (unset)
  SHELL=/bin/tcsh