ixwebhosting php mail() issues with subject

I encounter a very strange problem with ixwebhosting.

I am able to send email using the php mail() function with $subject = "test";

But if $subject = "testing of information send"; then i won't be able to 开发者_开发技巧receive any email

But actually "Mail sent!" was displayed in the php page.

if (!mail($email, $subject, $body, $from)) { echo "Error Sending Email!"; }

else

{ echo "Mail sent!"; }

Is it possible that the email is being classed as spam somewhere down the track? Are you able to get logs from the mailserver indicating whether mail gets sent?