Thread throwing an Exception

Hello, I got this code from David Reilly's site. What this prog does is
terminate the prog after a specified time. What I want to do is just
throw an Exception to be caught by other java programs. I tried to
throw an exception in timeout (ex. timeout() throws Exception) and run
(ex. run throws Exception) methods but it is not allowed. Please help.

import java.net.*;

public class Timer extends Thread
{
    /** Rate at which timer is checked */
    protected int m_rate = 100;

    /** Length of timeout */
    private int m_length;

    /** Time elapsed */
    private int m_elapsed;

    /**
      * Creates a timer of a specified length
      * @param length Length of time before timeout occurs
      */
    public Timer ( int length )
    {
        // Assign to member variable
        m_length = length;

        // Set time elapsed
        m_elapsed = 0;
    }

    /** Resets the timer back to zero */
    public synchronized void reset()
    {
        m_elapsed = 0;
    }

    /** Performs timer specific code */
    public void run()
    {
        // Keep looping
        for (;;)
        {
            // Put the timer to sleep
            try
            {
                Thread.sleep(m_rate);
            }
            catch (InterruptedException ioe)
            {
                continue;
            }

            // Use 'synchronized' to prevent conflicts
            synchronized ( this )
            {
                // Increment time remaining
                m_elapsed += m_rate;

                // Check to see if the time has been exceeded
                if (m_elapsed > m_length)
                {
                    // Trigger a timeout
                    timeout();
                }
            }

        }
    }

    // Override this to provide custom functionality
    public void timeout()
    {
        System.err.println ("Network timeout occurred.... terminating " );
        System.exit(1);
    }
}