Como faço para enraizar meu Samsung Spica?
How do I go about rooting my Samsung Spica?
The main reference resource site for modders and "cookers" of Samsung Spica aka i5700 is at Samdroid forum board, here.
It contains all information you need to upgrade your firmware version, root your phone, etc.
This rooting tutorial is much easier to follow than Samdroid's (it still uses Samdroid's method, but the tutorial is much less terse and have pictures): http://www.addictivetips.com/mobile/root-samsung-galaxy-spica-i5700-with-leshaks-kernel/