glassfish crash caused by libdbus on debian squeeze - glassfish

Question

I'm running glassfish v3.1.1 build 12 using java build 1.6.0_29-b11 on linux debian squeez (6.0.4).
I'm running a webapp which is calling an external soap webservice.
Every now and then the jvm crashes. I can reproduce this crash by executing 20 threads simultaneously.
The hs_err_pid crash dump file shows that libdbus is the problematic library. Here's the interesting part of the crash dump
Stack: [0x00007f3fef0ff000,0x00007f3fef200000], sp=0x00007f3fef1f7058, free space=992k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
C [libdbus-1.so.3+0x28de0]
Java frames: (J=compiled Java code, j=interpreted, Vv=VM code)
j sun.net.spi.DefaultProxySelector.getSystemProxy(Ljava/lang/String;Ljava/lang/String;)Ljava/net/Proxy;+0
j sun.net.spi.DefaultProxySelector.access$100(Lsun/net/spi/DefaultProxySelector;Ljava/lang/String;Ljava/lang/String;)Ljava/net/Proxy;+3
j sun.net.spi.DefaultProxySelector$2.run()Ljava/lang/Object;+151
v ~StubRoutines::call_stub
J java.security.AccessController.doPrivileged(Ljava/security/PrivilegedAction;)Ljava/lang/Object;
j sun.net.spi.DefaultProxySelector.select(Ljava/net/URI;)Ljava/util/List;+273
j sun.net.www.protocol.http.HttpURLConnection.plainConnect()V+187
j sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect()V+9
j sun.net.www.protocol.http.HttpURLConnection.getOutputStream()Ljava/io/OutputStream;+134
j sun.net.www.protocol.https.HttpsURLConnectionImpl.getOutputStream()Ljava/io/OutputStream;+4
j com.sun.xml.ws.mex.client.HttpPoster.post(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;)Ljava/io/InputStream;+60
as you can see the actual HttpPoster.post is being called after which the crash occurs. The sun.net.spi.DefaultProxySelector is part of rt.jar so this is part of the default jvm installation.
I tried jdk7 but also here the crash occurs.
Then I installed openjdk which also crashed.
Then I installed dbus-java which is the java implementation of dbus (using apt-get). Normally this library is only used when certain jar files are put explicitly in the path. But after installing this library the crashes don't occur anymore. So it looks like openjdk is using this library (assumption)
I talked to the maintainer of dbus-java and also he is not aware that sun jdk or openjdk is using dbus. So we are both quite confused.
The crashes don't occur anymore but now the admin interface of glassfish stops working. Googling shows that this is a known issue and the solution is to start using sun jdk. Aaargh.
Have you seen this problem before? Is there a solution?
UPDATE:
the DefaultProxySelector.getSystemProperty method is the last method that is called before a native method is called. Looking at the code of DefaultProxySelector I found that this method should only be called if the java.net.useSystemProxies=true. But this property is not set (no -D setting in the jvm settings) nor is it true in the $JAVA_HOME/jre/lib/net.properties file. But after debugging it shows this boolean IS true.
So the big question now is : why is this boolean true?
UPDATE 2:
The problem was caused by the updatetool configuration. See bug report GLASSFISH-18360 for details.