From what I've read online there's no free way to unlock the Tocco Lite.
I did, however, find
this site.
I personally don't trust these sites, but it seems like your only option. It has a pay by paypal method, so there's nothing to lose really.
If, however, you want to find a different site, feel free to google "remote unlock Samsung S5230" and have a read of the sites that come up.
BE ABSOLUTE SURE YOU READ REVIEWS OF THE SITES BEFORE PARTING WITH MONEY!
Just thought I'd add that in, since I don't want to be held responsible for anything.