uploadInfo is from CGI.pm, so you want the source from the CGI module?
That would be the relevant code, yes. Not being a frequent CGI programmer, myself, I didn't recognize that it was a CGI function. So here's the source: 
sub uploadInfo {
    my($self,$filename) = self_or_default(@_);
    return $self->{'.tmpfiles'}->{$filename}->{info};
}

[download]
It's a method, and you're calling it as an ordinary sub.

Update: as dragonchild points out, that's not the problem. So the critical issue looks like: what is the value of $filename? It may require some exploration and dumping of data to see what value it should have in order to work.

Caution: Contents may have been coded under pressure.

In reply to Re^3: IE vs. Firefox : Can't use an undefined value as a HASH reference error by Roy Johnson
in thread IE vs. Firefox : Can't use an undefined value as a HASH reference error by hmbscully

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