How to chain DBIxs

How can you use two DBIx::xxx at the same time?

Say I had DBIx::fred and DBIx::bloggs both providing different
extensions to DBI which do not interfere with each other. Both
DBIx::fred and DBIx::bloggs do a:

DBI->connect

when what I really want to do is:

my $dbh = DBIx::fred->connect()

and DBIx::fred internally does a:

my $dbh = DBIx::bloggs->connect which does the DBI->connect.

Is there a defined way to do this with a DBIx module? or are you stuck
only using one DBIx module unless you edit them? Perhaps no one has
needed or wanted to do this before.

Martin