$ ls -l /tmp/ikegami/foo
-rwx------ 1 ikegami pg1404028 30 2011-01-04 12:23 /tmp/ikegami/foo*

$ cat /tmp/ikegami/foo
#!/usr/bin/perl
print "bad\n";

$ /tmp/ikegami/foo
-bash: /tmp/ikegami/foo: /usr/bin/perl: bad interpreter: Permission denied

$ /usr/bin/perl /tmp/ikegami/foo
bad