OK Here is what I did.
First set up the email at T-Mobile. Sign in to www.t-mobile.com and go to My Email. Follow the instructions to add your existing ISP or whatever email account. The system knows the pop and smtp servers for most email isps.
The sequence
t-mobile.com>sign in>MY Email>Setting>add new mail box
Follow the instructions they give.
Now when you are done with that go to Mailbox and where it has the "edit" or Delete" click on "edit"
Now on that screen look above the displayed mailbox name and you can click "Pop Settings"
Up will come a screen with all the required info you need input to your Phones email client.
It will look like this
E-mail Address: your pop email address
Mail Server (POP3): myemail.t-mobile.com
Outgoing Mail Server (SMTP): myemail.t-mobile.com
User ID: XXXXXXXXXX:1 this is your phone number with :1 behind it
Password: Password OK You need to create a pass word it can be the same as the email account or whatever. This is your login in to t-mob.myemail not to the t-mobile site
By the way if you add more pop emails the userid for the phone will be your number and :2 or :3 etc. Only thing is you will have to use an Email Client like Sunnsoft (works great) to handle more than the 1 account limitaion of the phones standard email client.
Anyway now go to your phones email client.
I assume you will use the outlook provided with the phone. Go to "Menu"
> "Options" > "Email Setup" Click Next
Enter whatever name you sign the account with Like Smeg36 or Joe
Enter the pop email address like smeg36@smeg36.com
Server Type >pop3 (most likely)
Click next
Incoming Server : myemail.t-mobile.com
Outgoing Server: myemail.t-mobile.com
Network: The Internet (I assume you have that working ok)
Click next
Username: XXXXXXXXXX:1 your phone number followed by which pop account you want to check. Something to note: I migrated my phone number from ATTWorthless Services but my myemail account id is still the orginal number that t-mob assigned me. Now that may seem like a hassle-I am sure they can change it but it works and that is all I care about. That is why you need to do the edit above to see your user id.
Password: This is the password that goes with the userid not you pop email password. You create this in myemail.
Domain: leave empty
Check Save password unlesss you want to enter it all the time.
Click Next and Finish
You should be good to go.
Now if you want to use multiple accounts Sunnsoft Mail Center works well. One other thing to note:
The T-mob myemail will periodically sync with you isp email account. You can set alerts to message your phone (SMS) when a message is found in the que. See Alerts in myemail on the T-mob web site. It works fine
Also after you do the settings T-mobile make take some time to set the servers etc. Send your self an email and test.
Also the t-mob site says to Note: Please check the "My outgoing mail server requires authentication" option in your POP client. This option might not be supported by all e-mail clients. I didn't need to. That is in the email client Send options.
Good Luck