channel4 is a bit harder than itv. so here another proof (screenshots), ta-rah!
GOOD NEWS. getflv posted an updated version on their website (today!!):
GetFLV Version 9.0.0.0,
and with it i was able to download the video!! 
the FIRST (line#1) and the LAST line (line#6) belong to the same (actual) video clip. the url's in between, lines #2-#5, belong to the ads (commercial clips of ~40secs length). i waited until all ads were gone and until line#6 appeared. then "Download" and GFLV begins to download the video without problems.
GFLV downloaded the following url:
Code:
rtmpe://ll.securestream.channel4.com:80/a4174/e1/?ovpfv=1.1&e=1301338326&ip=178.238.142.242&h=b7e0c6f007f45b95f92a06f11929438f
!!GREAT JOB AND BIG THANKS GOES TO THE GETFLV SUPPORT TEAM!!