Hi,
I've upgraded my spica to 2.1 according this guide:
Sameer Prabhakar - Mad Ramblings: Samsung I5700 (Galaxy SPICA) Android 2.1 Flashing Guide (Updated) only had to leave out the csc part. Was able to install live wallpapers from the market, but i needed to install the LiveWallpaperPicker.apk mentioned in this guide:
Sameer Prabhakar - Mad Ramblings: Rooting & other goodies on the Samsung Galaxy SPICA I5700 (2.1 Firmware)
Unfortunately after that the live walpapers are currently only appearing at the lock screen, on the home screen it has the static walpaper set.