in reply to sendmail *grumble*
from the command line causes it to process the queue once, then exit. Add the -v switch to make sendmail chattier while it does it. Normally a sendmail daemon only queues under difficulty, it should process the mail immediately without queuing unless it has been configured to do so. You can add a time argument to -q:
processes the queue every hour.
Check out sendmail.org for further documentation. You may have to invoke the -d debugging switch to see what sendmail sees.