Not sure what what upaint is but if it's an unreal app try installing maya ple that's on disk 5 if you have it on cd or "disk 5" folder if you have it one one DVD. You can then open your normal maya files in this. Then you will also find an UT2004 export plugin on the same disk or folder that you can install to PLE. This might let you export to one of those files, but as i've never used this upaint i might be wronge.
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