error -10 bitcoin is downloading blocks

[zxasqw]

hi fellas!

i've downloaded the oficial client from bitcoin.org. after that i've started it from console in an attempt to make the server run. It does run, but typing 'bitcoin.exe getwork' outputs the error i mention above...

and gui miner doesn't seem to be mining.

do i have to wait all blocks to be downloaded in order to start working? how long does that take?

just for the record i want to do some solo mining, using a windows XP machine for tests.

thanks!

droope