The error:
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checking for utf8_mime2text signature… new
checking for U8T_CANONICAL… no
configure: error: utf8_mime2text() has new signature, but U8T_CANONICAL is missing. This should not happen. Check config.log for additional information.
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The fix:
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yum install libc-client-devel
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Officially Plesk 9 does not support  ClamAV (Parallels as of the time of writing officially supports two antivirus solutions that needs you to pay for the license )
The integration uses Plesk9- Postfix - ClamSMTP - clamAV to get things working.This was accomplished in a CentOS -5.2 system .But it should work just fine on other [...]

Scenario :- Error while sending email using Squirrel Mail :-
Message not sent. Server replied:
Connection timed out
110 Can’t open SMTP stream
This problem usually occurs when CSF ( Config Server Firewall ) is installed on your server and it is interacting with the working of squirrel mail. So while configuring CSF enable both SMTP_BLOCK & SMTP_ALLOWLOCAL . [...]

The following command lists exim MTA’s version number .It also prints out the DBM library being used,the optional modules being used and drivers included in the binary
It also displays the name of the run time configuration file being used
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exim -bV
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