You forgot the ! in your shebang.

#/user/bin/perl -wT
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So it works from the command line when you specify the perl interpreter, but fails via CGI with that incomplete invocation. You need this:

#!/user/bin/perl -wT
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It happens =)

Update: If it still doesn't work you have some other more exotic problem. I tested your code and form and it didn't work until ! was added.