Yes. You will need to create the new settings for mmode GPRS also so your Internet connection is working.
I found some information for mmode in WM2003SE which I edited for WM5. Haven't personally tried it but hope it works for you. However if the MMS message sent to you was too old it might not get delivered as it only stays on the network for some time.
Good luck.
AT&T GPRS, WAP/mMODE, & MMS settings
1) Start>Settings>Connections>Proxy
2) Delete MEdia Net Settings.
3) Menu>Add
4) Create PROXY CONNECTION:
Description: mMode
Connects from: The Internet
Connects to: WAP network
Proxy (name:port): 10.250.250.54:8080
Type: HTTP
Username: (blank)
Password: (blank)
5) Open GPRS Connections.
6) Start>Settings>Connections>GPRS>Menu>Add
Create a new GPRS CONNECTION
Description: AWS GPRS
Connects to: The Internet
Access point: proxy
User name: (blank)
Password: (blank)
Primary DNS: (blank...will later default to 0.0.0.0)
Secondary DNS: (blank...will later default to 0.0.0.0)
IP address: (blank)
7) Start>Settings>Connections>Menu>Advanced
DATA CONNECTIONS
Internet Connection: AWS GPRS
Work Connection: Automatic
WAP Connection: AWS GPRS
Secure WAP Connection: Automatic
8.) In Internet Explorer, Menu>Tools>Options>Connections
Auto Detect Settings: Unchecked
Select Network: Wap Network
9) MMS SETUP.
Inbox>Menu>Options>Account Options>MMS>Menu>MMSC Settings.
10) Menu>New
Name: AWS MMS
MMSC URL:
http://mmsc.mobile.attwireless.net
WAP Gateway: 10.250.250.100
Port: 9201
Connect Via: The Internet
Max. Sending Size: 100K
WAP Version: WAP 1.2
Click Done
Menu>Set as Default
11) Click Back Arrow to return to the MMS Preferences Screen
Check the following boxes:
Retrieve Immediately
Save sent messages
Allow delivery report
Allow read report
No. of Attempts: 3
Photo Resolution: Original Resolution
Click DONE.
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