This can be done after a firmware update.
This is done at a SonyEricsson Service point
(for free if you can show a recept).

I don't know the exact method, but you can read
more about is on the www.myt610.com www.myt610.net forum.
(Somewhere in the Firmware section)

If you want to check your current firmware:

( > = move right with the stick, < = move left, * = the * a/A key)

There you will see a SW menu option. (with the version number)

I had R1L013, they upgraded it to R3C002 (latest release by SonyEricsson)

This firmware has some other improvements for the T610:

--30% JAVA speed improvement (JBenchmark test) e.g JAVA applications run
much better and smoother. Now we can load more java games and do not
have to to settle for mophun too much

--New menu in "Send Message" called "Contacts", saves you one click when
sending messages

--When you play recorded conversations, they now play over the
loudspeaker (better quality playback then before (the mms method))

--Pictures taken with the camera appear to take up less memory! (avrg
14kb-19kb for large size photo)

--Pictures taken with the camera appear to be clearer (might have to
play around with shutter speed)

--When choosing word alternative in T9 while replying to message,
pressing the joystick in will no longer send the message, but accept the
word. (Finally!) While not in T9 word selection, joystick in will send
the message.

--When previewing ringtones from "My sounds" they start at maximum volume

---If vibration is turned on, the phone will now vibrate on calendar/timer

-- Camera looks pictures look sharper and better. In R1A, only
brightness control (Up and Down joystick on camera mode) is available.
Now, saturation control (Left and Right on joystick on camera mode) is
already available.

--In checking memory status, My sounds memory usage is now reported. In
R1A, the total memory is reported as "0kb" and you have to click on the
My sounds to get a listing of sounds with the corresponding memory usage
per sound.

-- Menus load a lot faster. Delay in response is hardly noticeable

-- Clock on standby screen has more rounded font.

--Now you can copy individual phonebook entries from the SIM to the
Phone's memory. This is done via Phonebook->Advanced->Call from
SIM->then select the contact you want->More->Copy to phone. No facility
yet to copy individual contacts from phone to SIM.

Hope this helped somewhat:)

Maurice - The Netherlands