I discovered this trying to make a REST dispatch in a .cgi script. I believe you're right -- that DELETE can be handled just like GET. On my system, I made the following change to CGI.pm, and DELETE started to work (I got query string parameters back).

--- /usr/local/share/perl/5.10.0/CGI.pm.bak     2009-11-05 15:26:07.00
+0000000 -0700
+++ /usr/local/share/perl/5.10.0/CGI.pm 2009-11-05 15:23:05.000000000 
+-0700
@@ -649,7 +649,7 @@ sub init {

      # If method is GET or HEAD, fetch the query from
      # the environment.
-      if ($is_xforms || $meth=~/^(GET|HEAD)$/) {
+      if ($is_xforms || $meth=~/^(GET|HEAD|DELETE)$/) {
         if ($MOD_PERL) {
           $query_string = $self->r->args;
         } else {
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This is a pretty minor modification, and you get decent functionality out of the DELETE verb (i.e. parameters). I'd love to see at least this much provided by CGI.pm.