It bombs, in 10.4.11, with java 1.5:

===== Saturday, April 19, 2008 3:03:01 AM Asia/Seoul =====
FinderPop-ppc-20932: Patching 'Spongefork' 0:580001 (CF)
Spongefork 3.3.3 (4.18.08)
�1999-2008 Ryan Francesconi
[SF] java.version 1.5.0_13-121
[SF] Sat Apr 19 03:03:06 KST 2008
getAppJarPath() /Users/qwertypoiuy/Desktop/Spongefork_3_3_3/Spongefork.app/Contents/Resources/Java/Spongefork.jar
getPrefsFile() /Users/qwertypoiuy/Library/Preferences/Spongefork/com.spongefork.app.Spongefork.properties
* no license found
SplashFrame.actionPerformed() try button pressed
SplashFrame.actionPerformed() starting init() thread
Spongefork.init() creating windows
getAppJarPath() /Users/qwertypoiuy/Desktop/Spongefork_3_3_3/Spongefork.app/Contents/Resources/Java/Spongefork.jar!/Resources/help.rtf
Spongefork.init() menu bar
Spongefork.init() initJSyn()
EXTS: /System/Library/Java/Extensions
JSyn using native library JSynV144
CSyn 14.4 (C) 1997-2007 Phil Burk, Mobileer Inc built on Dec 23 2007 at 15:33:04
JSyn for OS X, Built on Dec 23 2007.
JSynAudioDevice.gatherAudioDeviceInfo() 2 devices, sys input id[1] sys output id [0]
Synth.DEFAULT_FRAME_RATE: 44100.0
Synth.RATE_AUDIO: 0
attempting to start Built-in Audio 0-1
/Users/phil/Work/jsyn/JSynXcodeProject/JSynV142/../../../portaudio/pav19/src/common/pa_process.c:1435: failed assertion `(bp->hostInputFrameCount[0] + bp->hostInputFrameCount[1]) == (bp->hostOutputFrameCount[0] + bp->hostOutputFrameCount[1])'