sed/awk-adding numeric to a column

I have a txt file as follows

Code:
Oct 1 file1 4144
Oct 1 file23 5170
Oct 2 file5 3434
Oct 21 file56 2343

I need to add a new column by marking the right log file from current directory. For example populate like this. Please not in the second columt for "1" it has associated log file as "01"

Oct 1 file1 4144 server.log.2009-10-01
Oct 1 file23 5170 server.log.2009-10-01
Oct 2 file5 3444 server.log.2009-10-02
Oct 2 file5 3234 server.log.2009-10-02
Oct 2 file5 3534 server.log.2009-10-02
Oct 20 file5 3434 server.log.2009-10-20
Oct 21 file56 2343 server.log.2009-10-21

I am hoping this can be easily done with SED ?

$ cat data
Oct 1 file1 4144
Oct 1 file23 5170
Oct 2 file5 3434
Oct 21 file56 2343

$ awk '{printf("%s server.log.2009-10-%02u\n", $0, $2)}' data

Oct 1 file1 4144 server.log.2009-10-01
Oct 1 file23 5170 server.log.2009-10-01
Oct 2 file5 3434 server.log.2009-10-02
Oct 21 file56 2343 server.log.2009-10-21

This version is hardcoded for Oct, but with just a tiny bit more smarts, it can be made to work for any month.

Regards,
alister

Awesome...works like a charm