Instead, follow the (widely available) instructions for importing the third-party library, then adding it using Build Path (which makes it known to Eclipse for compilation purposes). Here is the step-by-step:

1. Download the library to your host development system.
2. Create a new folder, libs, in your Eclipse/Android project.
3. Right-click libs and choose Import -> General -> File System, then Next, Browse in the filesystem to find the library’s parent directory (i.e.: where you downloaded it to).
4. Click OK, then click the directory name (not the checkbox) in the left pane, then check the relevant JAR in the right pane. This puts the library into your project (physically).
5. Right-click on your project, choose Build Path -> Configure Build Path, then click the Libraries tab, then Add JARs…, navigate to your new JAR in the libsdirectory and add it. (This, incidentally, is the moment at which your new JAR is converted for use on Android.)

Ref: http://stackoverflow.com/questions/3642928/adding-a-library-jar-to-an-eclipse-android-project