Recently, I was involved in deploying two solution packages I had created. The farm administrator had just used the the Solution Management page in Central Admin to deploy the packages globally, and the status was "Deploying" but more than the usual amount of time went by and it was still listed as Deploying.
To resolve this, we first ran stsadm -o execadmsvcjobs on the server running Central Admin. No change. We then ran stsadm -o execadmsvcjobs on each member of the farm that had OWS Timer (sptimerv3) on it (everything included Reporting Sevices Servers, but not the database servers used only on the back end).
At this point, one solution package completed, but the other still did not. We restarted the OWS Timer Service (sptimerv3) on each member in the farm (again, everything that had OWS Timer on it). At that point, both packages completed their deployment and all was well.