[Exim] ACL Problem (require verify = header_sender)

After a in general painless migration from exim-3 to exim-4
(thanks to the great work of convert4r4) I've a small problem with ACL:

My configuration containsi in the ACL section:

| acl_smtp_data = check_message
|
| ...
|

|  check_message:
|    require verify = header_syntax
|    require verify = header_sender
|    accept

Some user agents (netscape for example) send a header containing

    Sender: username

These mails are refused by the exim server.

How to overcome the problem ?

Regards        _______________________________________________________________
Frank Elsner  /                         c/o  Technische Universitaet Berlin   |
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