[Exim] Exim 3.35 not seeing a header

my filter does

testprint "Return-path= $h_Return-path: Been there = $h_X-BeenThere:"

my message has the followinf as the first lines

Return-path: <exim-users-admin@???>
Envelope-to: spamfilter2@???
Delivery-date: Sat, 08 Jun 2002 23:02:54 +0200

yet the testpritn comes back with

Testprint: Return-path= Been there = exim-users@???

WHY isnt it seing the Return-path in the message?