External Control of Communication Channel don't work

hello everybody,

i'm working with PI 7.01

I want activate external control for communication channel following this document:

http://scn.sap.com/community/pi-and-soa-middleware/blog/2011/05/24/startstop-a-communication-channel-from-an-abap-program-using-the-external-control-switch

In dev system it work perfectly!

But in PRD no.

when i launch the link in prd i have this error:

You are not authorized to view the requested resource.

I'm using the same procedure. I check the user and he have same permissions and same roles.

What to do?