Odd Perl interpreter problem

[greenberg at hcfama.org (Josh Greenberg)]

I am having an odd Perl problem on Slack 8.0 box.

I have #!/usr/bin/perl as interpreter line in scripts.
I get "bad interpreter: no such file or directory" messages when trying to 
run the script.
which perl gives /usr/bin/perl
I can run the script "manually" -- e.g. by entering /usr/bin/perl scriptname
File permissions are fine

Anyone have any ideas how to fix -- probably something dumb, but annoying...

Thanks.