BUG #8116: create trigger after insert fails if procedure being executed is having error

The following bug has been logged on the website:

Bug reference: 8116
Logged by: CREATE TRIGGER AFTER INSERT FAILS
Email address: nitinmn(at)gmail(dot)com
PostgreSQL version: 9.1.7
Operating system: WINDOWS , UNIX
Description:

when we create a trigger for a table which basically runs triggers a
procedure after insert.now if the procedure has some error when executing ,
the insert also fails, But ideally since this trigger is defined after
insert , the insert should have been successful.
eg
CREATE OR REPLACE FUNCTION insert_send_mail_function()
RETURNS "trigger" AS
$BODY$
use Mail::Sendmail;

$str = substr trim($_TD->{new}{url}),3;
$subject = "Login Alert : ".$_TD->{new}{username}.", ";
message = "URL accessed: ".$_TD->{new}{url}."\n";
%mail = ( From => $_[0], To => $_[1], Subject => $subject , Message =>
$message);

sendmail(%mail) or die $Mail::Sendmail::error;
return undef;
$BODY$
LANGUAGE 'plperlu' VOLATILE;

CREATE TRIGGER insert_send_mail_trigger
AFTER INSERT ON user_log
FOR EACH ROW
EXECUTE PROCEDURE insert_send_mail_function('abc(at)gmail(dot)com',
'ab1213(at)gmail(dot)com');

because there is a trim function , thought the procedure gets parsed
successfully , while runtime it fails , but that should not stop insert
failure since it is only after insert.