The first question is if you are migrating a ScreenOS config or a JunOS config. If you are migrating a ScreenOS config, the process is rather simple and can be done with the use of notepad/word to do search and replaces for key words and excel for re-ordering columns (ScreenOS puts the permit after the services, we put it before the services, etc). I have helped with a few migrations myself using this process and have found it much more reliable than even Juniper's ScreenOS to JunOS tool. (Perhaps because it is a firewall-firewall migration, as opposed to a firewall-router migration.) Your account team can provide you with documentation to support this process.
Now, if you are migrating a JunOS config to an ASA config, there are also tricks that allow you to do it. However, it is not as straight forward as the JunOS config looks very different. This process is most efficiently done using the output of some show commands rather than the config itself. In this case, I would strongly recommend you contact your account team for more details.
In either case, welcome to Cisco's firewalls. I am sure you will feel like one who has emerged from black and white movies to technicolor!!
:-)
Maria
