Special Characters in "To" address causing crash

[Calator]

Hi,

We use sendmail to send messages that are automatically generated from our business systems software.

This process has crashed when sendmail encountered a destination address that was containing an apostrophe, eg:
john.o'rourke@mydomain.com

I have 2 questions:

1. what are all possible ways to prevent the crash?. Eg escaping the apostrophe: \', or are there any other methods such as enclosing the whole address within other separator characters: eg "address" ?

2. what are all other special characters that will confuse sendmail apart from apostrophe, that we need to take care of?
Many thanks

 

[danielhozac]

Apostrophes aren't allowed in usernames. Simple as that.
To find out what characters are allowed, check the SMTP RFC. //Daniel

 

[Calator]

Daniel,
Thanks for pointing me to smtp rfc 821. This showed that special characters including apostrophes are allowed in user names and may be escaped using "\" or better still, using the quoted text format which means to enclose the address within triple double-quotes: """address""". Tested both avenues and found to work.