Yes, the full error message is more-or-less self-explanatory. Personally, I'd just use CGI in OO mode, eg:

use CGI;
use LWP::Simple;

my $cgi=new CGI;
# LWP's head()
print head();
# CGI's head
print $cgi->head();
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...and of course you can use 'require CGI' instead of 'use CGI', which could have potential benefits.