There seems to be a regression 1.3.1_09 and in 1.3.1_10.
A Thread.interrupt() call no longer executes after first try.

Using 1.3.1_08 or version earlier the expected behavior is seem:

greatpoint> /net/koori.sfbay/a/v13/jdk/1.3.1_08/fcs/binaries/solaris-sparc/bin/java test.InterruptThread
 +++ Poller.run
 @@@ it is running
 +++ poller interrupted!
 @@@ it is running
 @@@ it is running
 +++ poller interrupted!
 @@@ it is running
 +++ poller interrupted!
 @@@ it is running
 +++ poller interrupted!

But running the same testcase with _09 and _10 the Thread.interrupt is passed
over:

greatpoint> /home/atongsch/JDK/1.3.1_09/j2sdk1_3_1_09/bin/java test.InterruptThread
 +++ Poller.run
 @@@ it is running
 +++ poller interrupted!
 @@@ it is running
 @@@ it is running
 @@@ it is running
 @@@ it is running
 @@@ it is running
 @@@ it is running
 @@@ it is running
^Cgreatpoint> /net/koori.sfbay/p/v10/jdk/1.3.1_10/fcs/b02/binaries/solaris-sparc/bin/java test.InterruptThread
 +++ Poller.run
 @@@ it is running
 +++ poller interrupted!
 @@@ it is running
 @@@ it is running
 @@@ it is running
 @@@ it is running
 @@@ it is running
 @@@ it is running
 @@@ it is running
 @@@ it is running
 @@@ it is running


The testcase is located in the attachment