Yep. Its a pain when you don't have the date of birth of a profile you did not create...
A FIX... though pathetic that we have to do this...
1. Xbox 360 -> Download Madden NFL 12 from Xbox marketplace, its 1.5GB in size so give it some time
2. !!! DO NOT CREATE EA ACCOUNT ON PC... See next step.... !!!
3. PC -> Have an email account ready, one that has not been used on EA, such as a free one from mail.com, live.com...
4. !!! DO NOT CREATE EA ACCOUNT WITH THAT EMAIL ON PC... See next step.... !!!
5. Xbox 360 -> Select PLAY DEMO from menu. Next you should be shown the offending email address that is linked to your gamertag. Enter your new email address followed by your email password. It create your account with the EA servers.
6. PC -> Login to ea.com using the email and password you put in on the Xbox. Your gamertag shall be linked and you may now edit your profile.
PATHETIC that BF3 has not the option to verify email.
Unhappy end user