try this
1.  Go to the phone app
2.  Dial ##634# and click Send
3.  When prompted for a password type 277634#*#
4.  You should now be at "Factory Menu"
5.  Choose "Engineer Menu"
6.  Choose "Other Setting"
7.  Verify that "Set ADC" is set to Enable
8.  From the "Other Setting" page, choose "Set network profile"
9.  You should now be on the "Set network profile" page and in the bottom half of the window you should see a list of *.xml files.  These appear to be the  network configuration files.
10. Look at the filenames for the config files and take your best guess at which one to choose for your provider.  if you are on CELCOM. try to find a xml file which have CELCOM in it.

After you choose that *.xml profile, your MMS should be working.

Anyone here has issues pairing using BT?

The BT just keeps on searching but doesn't detect anything.

A) MMS Settings for Celcom LG Optimus 7

When I read first this thread, I did not try it b'cos of other comments said it did not work. Today I went to another forum and they suggested the same instructions. Decided to give it a try today and ..... whollaa ... been using my LG Optimus 7 since Celcom launced it last year ... I finally sent my first MMS 

As my own personal record I changed the last instruction as follows:

10. Look at the filenames for the config files.
      For Celcom, use "_PROV_CLM_MY_502_19.xml" (there are two xml files with CLM_MY ... do not use the other one)
      Note: Once selected the xml file turns into green color or whatever color you selected as Accent color under theme  setting.

Having completed instructions 1 until 10, try send MMS. When sending make sure your phone does not go into sleep  ... keep on pressing the screen (just to make sure since I disable the notification) ... I sent 3 x MMS to 3 friends ... 2 x MMS were successful and 1xMMS did not go through even after several retries ... must be network ... not sure 
B) Forwading SMS for LG OPTIMUS 7

In case someone is still trying to figure out how to forward sms ... it is in the manual. It stated as follows:

1. On the Start screen, tap Messaging and then tap the conversation that has the text message you want to forward.

2. Tap and hold a message and then tap Forward.

3. Type the person's name, mobile phone number or email address in the To: box.

4. Tap the message box, type a message if you'd like, and then tap Send


Hope this helps 

ps
Can't wait for WP7 update in Mar'11 

ive updated and my mms seem to worked!!! haha.. now i can receive and send mms

maybe this will help u.

http://wmpoweruser.com/lg-optimus-7-play-t...feature-demoed/