It's evil and bad and I'm sure there are many reasons why you don't want to do this, but you can use a CODEREF in @INC to do something like:

BEGIN
{
   @main::OINC = @INC;
   unshift @INC, sub {
                         if ( $_[1] eq 'CGI.pm')
                         {
                              @INC = ($_[0]);
                          }
                          else
                          {
                             @INC = ($_[0], @main::OINC);
                          }
                                                                      
+          
                          return undef;
                                                                      
+          
                       };
}
                                                                      
+          
use strict;
use CGI;
[download]

/J\