LM hash command

[mastercracker]

Assuming that your hashes has been extracted properly and not syskeyed, yes you have to crack both halves separately. They have to be on separate lines of your hash list. Use the -m 3000 and you should read about the custom charsets:

http://hashcat.net/wiki/doku.php?id=mask_attack

Also, hopefully your rainbow tables did cover the whole keyspace. To be sure, I would redo it by bruteforce using a GPU. It can be done in a reasonable time nowadays. Make sure you do include space as a character as well.