[imp] EACCELERATOR PHP Crash

[Kyle Bartosiak]

I've just recently installed Horde Groupware Webmail 1.0 and everything seems to be working except sending email.  Once I press the send button, I get a 500 Internal Server Error.  After reviewing my error logs, I found this: 

Premature end of script headers: /home/kbartorg/public_html/horde/imp/compose.php
[19194] EACCELERATOR: PHP crashed on opline 118 of popen() at /home/kbartorg/public_html/horde/pear/Mail/sendmail.php:130

Would anyone have suggestions as to how I can fix this?

Thanks!
Kyle