I find I can't run setuid perl script
when I do this on a Unix-like platform:

1.Create a file "setuid.pl" :
#!/usr/bin/perl -T
2.chmod a+x setuid.pl
3.chmod u+s setuid.pl

then i try

shell> ./setuid.pl
Permission denied.

hmm...it always come out with this,
and it's not because i don't have execute permission.
The message was sent by perl,
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