+1 !
So many replication issue with previous SEP version earlier than 11.0 RU7 so as Chetan said, I strongly recommend you to migrate to higher version.
But for sure, you need to fix that issue first.
Check in your SQL Server with the help of SQL Server Management Studio (if you installed it) the table named sem5_log or sem5_logs the table has probably reached the file size limit allowed for this table.
If so, try to activate the truncate directly on your MS SQL. If it's not possible then simply increase the file size limit allowed of this table.
At the same occasion, check if you do not have any other sem5 tables nearly full, increase them a litle bit it's still better to anticipate any future issue :-P
The tables that you need to increase more than any others if they're very close to be full are: sem5_db & sem5_content
Then try again your replication.
However, we should remind you that it's strongly recommended to keep your servers updated and to use same SQL Database version. From one you're using 2003 and another 2005, that's somewhat risky even if it has worked without any probleme before.
Keep us updated ;-)
Kind Regards,
A. Wesker