I think they are largely unnecessary in modern systems. The protocol was written expecting that the SC might be connected to ACS via a hundred feet of serial cable, where transfer integrity was error-prone. If you are using today's network hardware, I think you should feel free to run without them.
That being said, you can also edit C4/SIP/Sip.pm line 38 to:
our $error_detection = 1;
and see if that doesn't accomplish what you want. This can be considered a bug or TODO with the SIP implementation inasmuch as the example config file has attributes for "error-detect" that are not actually in control.
--joe
On Thu, Feb 26, 2009 at 5:14 AM, Luigi Ipsa <l.piccione@ipsa.eu> wrote:
I try to send message to ACS with checksum AZ option but on syslog i read:
Unsupported field 'AZ' in Patron Info message
Unsupported field 'AZ' in Checkout message