[Upgrading, Modifying and Unlocking] nht_max:
I think it doesn't matter what version of WM6.0 or what language the i780 has, the procedure to upgrade the OS to WM6.1 is pretty much the same. I myself just got here (I mean this i780 section, I've been here for a few years now) about a week ago, and I luckily found somewhere this easy-to-follow instruction to do the job. So, I think I'll just post it here for your convenience (I've edited the links, because the original version of the text got the links all corrupted).

Here you go:

Here are the full Instructions on how to get Russian ROMS then the E1 English firmware on your Samsung i780.

Requirements

-A Windows XP machine (This is vital as Mirage Updater will not work correctly on a Vista machine. If required run XP on VMWARE)

-USB Cable

-Samsung i780 Phone

-Russian ROMS

-English E1 firmware

-Mirage Updater

-Active Sync 4.5

Make sure your battery is fully charged just to be sure; over 80% charge worked fine for me.

(0) Download Mirage Updater: http://rs227tg2.rapidshare.com/files/110283700/dl/Mirage_LV_v1.8.rar

(1) Download the Russian ROM: http://rs346gc2.rapidshare.com/files/120197435/dl/i780PUHE1.7z

(2) Download the ROM that you want to upgrade your device's OS to. The link is in the first post of this thread (About this, I think you can try one of the ROMs there, but don't take it as your final settlement, because as announced, the next ROM's gonna be released on the next Monday, which is 9th of March 1009). Thanks inertiax3 a lot for your amazing job. The link for fast navigation is here: http://xdaforums.com/showpost.php?p=3268146&postcount=1

(3) Download Samsung USB drivers: http://www.internet-tools.co.uk/blog/wp-content/uploads/2008/01/blackjack_modem_driver.zip

(4) Download the ActiveSync 4.5 app from the Microsoft website. Google is your best friend here.

(5) Unzip these five archives to a directory on you machine.

(6) Run the ActiveSync install.

(7) Run the Samsung USB drivers application.

(8) Restart you machine.

(9) Switch off your phone and remove the battery, then insert the battery. Do not switch on yet.

(10) Launch Mirage updater. Select MIRAGE LV image as the profile.

(11) Select EBOOT+PDA+PHONE and select the extracted RUSSIAN .img file.

(12) Wait for the files to be read by the Mirage Updater.

(13) Click on DETECT.

(14) Switch on the phone while holding the ENTER and FUNCTION buttons (ALT BUTTON) (These are the two outside buttons on the keypad's third row down.)

(15) The phone will have the following message on the screen '[ Emergency Mode ] You must push the Detect button of the download application before you connect the usb port'.

(16) Connect the phone via USB to your PC.

(17) Wait until the image is written.

(18) The phone will turn itself off.

(19) Perform a hard reset of the phone by turning it on whilst pressing the red and green buttons.

(20) Press the 'Space' button to format the phone (This is the hard reset).

(21) There is no need to go through the phone setup procedure in Russian, just take the battery out and replace it.

(22) Turn the phone on in 'Emergency Mode' by holding down the ENTER and FUNCTION buttons (ALT BUTTON).

(23) Close the Mirage Updater and restart the app.

(24) Click on the PDA button on the app.

(25) Select the ROM you've downloaded in (2), it's a .bin file from it's un zipped directory file.

(26) Wait for the app to read the file then press DETECT button.

(27) Plug in the USB cable.

(28) Wait while the image is 'flashed' to the phone.

(29) Perform a Hard Reset again on the phone when it has turned off. (Battery out, battery in, Turn on with the Red & Green buttons, press 'Space'.) To be on the safe side, just do a soft-reset once this time.

(30) Enjoy the masterpiece.

Big thanks to the guy who've posted this instruction, because I got this when wandering the site, so I don't remember where is was exactly. But thank you a lot.

I hope I somehow help you with this. Have fun!