Logstash debug file is not created after deletion

Hi,

We are currently working on Logstash 1.5.4.
We enabled the logstash debug, using -l option creating the debug log file. But we observed that it grew large in size and so deleted the debug file. But Logstash is not creating a new debug file.
Is it how the Logstash supposed to work?
It creates a new Logstash debug file, when we restart the Logstash. But can't it create one without restarting Logstash.

Thanks.

Logstash's logrotate config (as shipped in the Debian package) looks like this:

/var/log/logstash/*.log /var/log/logstash/*.err /var/log/logstash/*.stdout {
        daily
        rotate 7
        copytruncate
        compress
        delaycompress
        missingok
        notifempty
}

This works, so maybe Logstash detects and acts on copy/truncate rotations but not rename ones?