I think the SCJA certification is an excellent certification to have on your curriculum vitae.
If you're interested in adding a little bit more to your knowledge base, a nice
IDE certification is good to have. It lets people know you can work with a development tool as well. Of course, most IDE's are vendor specific, but they're good to have.
SQL skills are great as well. Every job I've ever had required some knowledge of SQL and a database. Even just a college course in SQL looks great on a resume, even if it's not a full certification or diploma. You gotta know your basic select and inserts, and the odd join as well.
Above all, you've got to have the right attitude. You've got to show an eagerness to learn, and a willingness to solve problems. If you can show this type of enthusiasm to an employer, (and if it is genuine, it will show) then you will succeed in the industry, regardless of the number of diplomas or certification you have under your belt.
Best of luck!
-Cameron McKenzie