Hi,
and thats it, no error, just nothing more logged.
Sounds like a bad email address in your list, this has been discussed in the past, in fact I asked that the resume.php automatically delete the top record in the lm_sendq table at this point - because it's probably what is causing it...
Open up your PhpMyAdmin for your MySQL database, go the the lm_sendq table - find the top record and look up the user id (uid field), then go to your lm_users table and search for the user id (id field), just for clarity your going to search for id=(what you looked up as the uid field in the lm_sendq table).
Take a look at the email address for that user (email field), I'll bet it's bad, or the domain is unresponsive or down. Delete the top record from the lm_sendq (the one you just looked when you grabbed the uid field) and then run resume.php manually from the command line - sounds like you need to test it running properly anyway... that should resume you from where you are...
Then you need to get your CRON issues straightened out, here's the call I use:
*/2 * * * * /usr/bin/wget -O /dev/null -T 0 http://mydomain.com/mail/resume.php?pw=mypass 1> /dev/null 2> /dev/null
Note that I run it every 2 minutes, since I found that even every 5 minutes was severely slowing down my sending...
Good luck, let us know what you find...