I bought Nokia E61 recently. I liked the phone. I have downloaded blackberry client but I am not receving any mails. I am cingular service. I have received few emails initially but not anymore. I get the service books activation email from my blackberry web client but no emails from my business email (which is hosted on Yahoo). I am able to send emails from my blakeberry but not able to receice. If anyone of you are able to receive blackberry mail please help me. you can reach me at marcstans@yahoo.com

One way synchronization of yahoo email is only available if your service provider has upgraded to BlackBerry Internet Service v2.0, check with your service provider for availability. With one way synchronization, email that you read on your BlackBerry device is marked as read in your Yahoo! Mail web based account. The same is true for deleting messages. Replies that you send from your BlackBerry device are saved in the Sent Items folder of the integrated email address.

alternatively also try this

Yahoo! Messenger

Get Yahoo! Messenger by client by opening your Internet browser on your BlackBerry device and going to http://www.blackberry.com/yahoodownload.

From there, you will easily download the client and start messaging with friends.

Enjoy the familiar features from the PC version of Yahoo! Messenger, including emoticons, stealth-mode, and knowing when someone is typing!

Did you sign up for Blackberry Connect service with your service provider. If not, you're not going to get anywhere. Blackberry email services need to connect to RIM (Research In Motion)'s servers in Waterloo, Ontario, and require a special data plan to access them.