we recently started using Courier in production mode and have had a few users already get the "534 Message header size, or recipient list, exceeds policy limit." error when try to send out even small group emails. The reason I have been able to diagnose so far is that the users are using their address book, which adds some extraneous info into the TO: field other than just the email addresses, with allows it to pass the "bofh : maxrcpts" setting that we use of 99...but causes it to fail on the header size limit.

i've read through the list archive for the responses and saw the one patch available at:

http://sourceforge.net/mailarchive/message.php?msg_id=7102590

That patch references that it relates that the 5000 byte limit relates to the TO: field. Where newer posts like the one below relate that this limit is for any single line within the body that is more than 5000 bytes.

http://sourceforge.net/mailarchive/message.php?msg_id=10839189

So, my questions:

1) What is the logic behind the header size limit of 5000 bytes, since it seems it is not only to protect against too many recipients? Is it some memory reading issue?

2) One posting referred to a 500 byte limit that also generates this error, does anyone know if that was a typo?

http://sourceforge.net/mailarchive/message.php?msg_id=1910957

3) For anyone that has applied the above patch, does it seem to cause any problems with the reliable operation of Courier?

4) I searched through the changelog and couldn't find reference to this being changed, so does anyone if more recent versions of Courier either implement the patch above or allow this setting to be modified via a simple system setting instead of code change.

thanks for any help or tips someone can offer...i'm learning to be confident in reading through the code myself, so maybe i'll be able to diagnose this myself in time...but right now would appreciate it if anyone has easily accessible ideas.

thanks,