perl -wle 'BEGIN { $SIG{__DIE__} = sub { print "Catched SIGDIE: @_";ex
+it(-1) }} use utf8; /^\w$/;'
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Results in:

Catched SIGDIE: Can't locate object method "IsWord" via package "main"
+ (perhaps you forgot to load "main"?) at /usr/local/lib/perl5/5.6.1/u
+tf8_heavy.pl line 30.
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This code illustrates the problem: the eval() done by utf8_heavy.pl fails and calls the die-handler which is set within the BEGIN block. I think this should not happen, because the 'die' within eval() is in a different scope than the position where the Die-handler is set.