You are absolutely correct about the @ character. Microsoft Access' query engine will now allow you to use it unless it is either within a single or double quoted string, such as the following:

INSERT INTO foobaric (email,password) VALUES ("foobar@foobaric.com","a
+mbidexterous");
[download]

I don't know why this code is requiring cgi-lib2.pl and CGI, since similar header and footer functions are part of CGI as well.