guys finally i got eclair working in my fone gt5700. it is obviously an unofficial way but pretty easy. just search for guide "how to update firmware of spica" n you can do it yourself. you have to download a firmware 2.1 of any choice of baseband version and a ODIN application. i guess least chances of bricking your fone. if you are not dumbest in the world then go for it. you can do it easily as i did. eclair is great and finally bluetooth works in my fone. feeling like nexus! hahhaha....
any help regarding update, you can ask me. i will tell you exactly what to do.