You try to run a urpmi/rpm command and find out that your urpmi database is locked and don't know what to do. Here is a script you can execute to unlock it.
#!/bin/sh
if [ -f /var/lib/urpmi/.LOCK ]; then
rm -f /var/lib/urpmi/.LOCK
fi
if [ -f /var/lib/urpmi/.RPMLOCK ]; then
rm -f /var/lib/urpmi/.RPMLOCK
fi
Save the above code into a file called something like unlock.sh into a directory of your choice. Then perform the following command, as root, assuming you named the file unlock.sh
chmod +x unlock.sh
Then as root again from within the directory you saved the file perform the following command:
./unlock.sh
This should run the script and do what it needs to do to unlock your rpm/urpmi database.
