I'm pretty sure you're doing something else wrong.   As you can see below, MIME::Lite::TT::HTML is just passing through the respective hashref to TT2.  And TT2 can certainly handle HoHs (I've done it many times). 

$ pwd
/home/eliya/tmp/MIME-Lite-TT-HTML-0.04
$ grep -r TmplParams .
./lib/MIME/Lite/TT/HTML.pm:        TmplParams  => \%params,
./lib/MIME/Lite/TT/HTML.pm:=head2 TmplParams
./lib/MIME/Lite/TT/HTML.pm:    my $tmpl_params = delete $options->{ Tm
+plParams };
$ grep -r '$tmpl_params' .
./lib/MIME/Lite/TT/HTML.pm:    my $tmpl_params = delete $options->{ Tm
+plParams };
./lib/MIME/Lite/TT/HTML.pm:    $tt->process( $template->{html}, $tmpl_
+params, \$html ) or croak $tt->error;
./lib/MIME/Lite/TT/HTML.pm:        $tt->process( $template->{text}, $t
+mpl_params, \$text ) or croak $tt->error;

[download]

Could you show the code (with the HoH) you've tried?

In reply to Re^3: Perl CGI and Template Toolkit by Eliya
in thread Perl CGI and Template Toolkit by Perobl

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