since PhoneGap 1.0.0 it seems to support bada, even though it is not
announced on phonegap.com (maybe not tested thoroughly enough?)
Anyways for those you are interested: I created a tutorial to get
PhoneGap wokring with bada SDK 1.2.1.

The text you'll find below. As HTML document including screenshots
you'll find it here:
http://www.mediafire.com/?6ofx137dyr4g5tq

It's prepared to be included on http://www.phonegap.com/start. Maybe
those guys would like to add it one day.

Have fun!
Julian

1. Requirements

User account at Bada Developers (register here)
PhoneGap 1.0.0
Using older versions of the Bada IDE might be easier.

2. Install Bada IDE 1.2.1 (SDK)

Download and install Bada IDE 1.2.1 (requires user account)

Note: During installation language packs are loaded. Sophos Antivirus
might prevent extracting this archive because it detectsa Sus/
UnkPacker in file FGraphicsOpengl.sym. Setup continues without error
though. If possible, deactivate Sophos, if not, read below.

3. Setup New Project

On first launch, Bada IDE likes to install updates. Accept by clicking
OK. Program closes.
Launch Bada IDE again, then under the File menu select New > bada
Application Project

Enter some application name and choose "bada Web Based Application".
Next.

Next.

Samsung had the ingenieous idea that all application that are loaded
on a bada phone need to have a valid manifest. Even this test
application needs one.
So deselect "Default manifest file" and check "Create a new manifest
file". Login. (Do not click "Next" nor "Finish"!)

Find a name that does not exist. Click the blue "Next" button.
Set Application version and choose your bada API version. Generate.
Continue.

Choose the privileges for your application. Best, take them all so you
can use this manifest for all your test projects.
Click the BLUE next button.
Finish.
Download manifest.xml

Use the just downloaded manifest file.
Now press the gray "Next" button.
Continue pressing "Next" or choose "Finish".

Congratulations! The first step is done.
4. Hello World on simulator

Open your new project in your bada IDE workspace and the PhoneGap
archive.
Delete folders Icons, inc, Res, and src.
Copy these folders from the PhoneGap archive.
Open go to your project workspace in folder phonegap (e.g. workspace
\HelloBadaGap\Res\phonegap\) and execute phonegap.bat.
Switch back to bada IDE. Right click your new project and choose
"Refresh".
Again, right click > Properties

Enter valid image in all Type1 fields (e.g. "PhoneGap.png"). OK.
Again, right click > Build Configuration > Set Active > Simulator-
Debug
Again, right click > Build Project
If you get error "cannot find -losp_rt0" you probably did not
deactivate Sophos. In this case:

Navigate to your download folder (where bada_SDK_1.2.1.exe is).
Find archive "bada_SDK_1.2.0_Wave_LP1.zip"
Extract it to your <bada install dir>\Model (e.g. c:\bada\1.2.1\Model
\)
If the already is a fodler "Wave_LP1", delete it first. Just to be
sure.
Switch back to bada IDE.
Right click your project > Build Project
Again, right click > Run As > bada Simulator Application. (If
necessary, follow the setup procedure.)

In case of a failure, consult bada Help (e.g. <bada install dir>
\Documents\Tutorial\bada Tutorial.Development Environment.pdf).
If you see the PhoneGap application running in the simulation, but
nothing happens, make sure that you called phonegap.bat.
If compiling seems okay but nothing happens (program not uploaded,
Bada homescreen) and on pressing the keylock button the console
outputs: "[...] PHONESTATUS:00> Idle Entered", try starting KIES and
update your bada phone to the latest firmware version. Sometimes
restart your phone also helps.
5. Deploy on device

Connect bada Phone with USB cable to PC. Choose USB mode "USB-
Debugging". (Settings > Connections > USB)
Drivers can be found in <bada install dir>\Tools\Wave*.zip
If bada IDE can still not find phone, check Windows' Device Manager.
Install for still unknown devices the same source.
Right click the project > Build Configuration > Set Active > Target-
Debug
Again, right click > Build Project
Again, right click > Run As > bada Target Application

Done!