After upgrading to Mac OS X Lion, unable to sent the mails using MobileMe.

I am having issue afire I had upgraded to Lion, the issue is that I can no longer send an e mail using my MobileMe account from my MacBook Air. Ehile trying to do this, I see that Mail spins aways for several minutes trying to send the message before finally displaying a pop up that the mail could not be sent using a standard port. This worked fine in Snow Leopard. And also I see that Sending from my upgraded iMac on the same MobileMe account works fine the problem only occurs in my iMac. Can anyone help me in this case?

For this thing i will recommend you for the things which are as, while you are trying with mails at that time, your Mail's preferences, go to accounts and check you outgoing mail server. My mail wich are going out from the server authetication had been set "none" after upgrading to Lion. I am telling you this things because I have done the same thing to resolve the same problem in my case, I reselected my elderly settings from the drop down list and I could send messages again.

Hey thanks for the proper suggestion for working with the mobileme mail account. I tried with them and after this I found that removal of my mobileme mail account, quitting mail, then re-opening and adding my mobile me account again seemed to work for me. And here I see that mail is now sending from my mobileMe account again, although it still took an unusually long time to actually send the message. And here I would like to say thanks to all of y6ou for support me. Now I can basically sign the messages & get working back all the things again. To my knowledge I have never set up a certificate, which could document why the message would pop up. Why the dialog box flashes so quickly on the screen is still a mystery.

I was also having the same problem and after searching for the suggestion I came here to know that one user was having this type of the problem and after trying with the steps which are there he get his MobileMe working again. but after trying I came to know that it not working in my case. And still I am unable to sent the mails using MobileMe. Suggest me if any of you having the better suggestion related with this problem.