allow,RELAYCLIENT="",RBLSMTPD="",SENDER_NOCHECK="1"

[#1]

Two problems I could do with solving.
One of my regular correspondents (a family member) gets e-mails addressed to me returned to him with the following messages attached. QUOTE
5.1.0 - Unknown address error 571-'sorry, sender address
has invalid format (#5.7.1 - chkuser)'" errors, especially from people with
Blackberry devices. What can I do?
The sender is using an illegal character. In Blackberry's case they're using
a spam firewall that uses the slash character (/) in the sending email
address when messages are sent from the Blackberry device, regardless of the
reply-to address. To work around this you can either recompile chkuser to
allow for the illegal character, or turn off chkuser checks for their mail
servers. Below is my tcp.smtp file which includes all Blackberry mail
servers I have found (a couple are ghosts, and do not appear in DNS for the
record):
204.187.87.61:allow,RELAYCLIENT="",RBLSMTPD="",SENDER_NOCHECK="1"
Note I have edited this list for sake of band width in reality it is very long.
UnQUote
This happens spasmodically but far more regularly my Plusnet spam filtering system puts his e-mails in the spam can.  No matter how often I tell the system that it is NOT spam.  Is there  a patch or something we can do to eliminate these annoying problems by may be adjusting his messages so as to be better and more regularly recognised by the Plusnet systems?  He uses Firefox.
Sorry to post here but I have searched the Forums and Googled  without much luck. By Googling I  get some very technical stuff which I cannot follow.  Nothing showed up following a search of this forum so I guess I might be alone with this problem.
Many thanks for reading this far
Mike Harding

[#2]

Quote

Is there  a patch or something we can do to eliminate these annoying problems by may be adjusting his messages so as to be better and more regularly recognised by the Plusnet systems?

You'll be able to whitelist based on sender address soon but I'm not sure the system will allow this if the SMTP transaction presents this address with a forward slash in it (assuming I'm reading the problem correctly).
Seems to me like a hiccup between the Blackberry and the Spam firewall as I'm pretty sure what it's doing isn't RFC compliant.
As for a solution (aside from the obvious ones), I'm at a bit of a loss TBH.

[#3]

Many thanks for your help.  I look forward to the 'whitelist' facility.
Mike Harding