jailbreak

the new firmware 2.1 of iphone and iphone 3G
First connect iphone and install the latest update of FW 2.1 with itunes
the download these files
iphone firmware 2.1 with can also be found in your computer if you have updated you phone with it using itunes
just serch for the file in my computer for file
iPhone1,2_2.1_5F136_Restore

or download it from this site :

appldnld.apple.com.edgesuite.net/content.info.apple.com/iPhone/061-5202.20080909.gkbEj/iPhone1,1_2.1_5F136_Restore.ipsw


then download the quickpwn application
from this link:

www.iphone-hacks.com/download.php?id=151

just install the application
and then follow steps in the application
this works 100%
i have done it for atleast 7Iphones both 3G and the old ones it work best
the installer and cydia is ready start downloading and installing applications from there using wifi
its cool man
if you like my post add my reputation
i am also attaching the quickpwn application
if you still have problems let me know i will try and help
Take care brothers cheers