Android build failed - java.lang.IllegalArgumentException: already added

Hi,

I use Titanium Studio 3.1.3 on Windows7, JDK1.6.0.45, Eclipse Juno Service Release 2(for modules).

I'm having a problem that I can't build my Android project. I get the following in the middle of a clean build.

[ERROR] UNEXPECTED TOP-LEVEL EXCEPTION:
[ERROR] java.lang.IllegalArgumentException: already added: Lnet/thirdparty/sdk/Const$1;
[ERROR]     at com.android.dx.dex.file.ClassDefsSection.add(ClassDefsSection.java:123)
[ERROR]     at com.android.dx.dex.file.DexFile.add(DexFile.java:163)
[ERROR]     at com.android.dx.command.dexer.Main.processClass(Main.java:490)
[ERROR]     at com.android.dx.command.dexer.Main.processFileBytes(Main.java:459)
[ERROR]     at com.android.dx.command.dexer.Main.access$400(Main.java:67)
[ERROR]     at com.android.dx.command.dexer.Main$1.processFileBytes(Main.java:398)
[ERROR]     at com.android.dx.cf.direct.ClassPathOpener.processArchive(ClassPathOpener.java:245)
[ERROR]     at com.android.dx.cf.direct.ClassPathOpener.processOne(ClassPathOpener.java:131)
[ERROR]     at com.android.dx.cf.direct.ClassPathOpener.process(ClassPathOpener.java:109)
[ERROR]     at com.android.dx.command.dexer.Main.processOne(Main.java:422)
[ERROR]     at com.android.dx.command.dexer.Main.processAllFiles(Main.java:333)
[ERROR]     at com.android.dx.command.dexer.Main.run(Main.java:209)
[ERROR]     at com.android.dx.command.dexer.Main.main(Main.java:174)
[ERROR]     at com.android.dx.command.Main.main(Main.java:91)
[ERROR] 1 error; aborting
[ERROR] System Error while compiling Android classes.dex

Seems that a SDK's class name is conflicting with something. The thirdparty SDK has a class called net.thirdparty.sdk.Const. Since it is in a jar file, I cannot modify it.

I'm stuck. How can I build the project? Thanks...