Netbank and Linux 2.4

 The Commonweath Bank's Netbank service works fine with Linux and Netscape 4.7 and later. However the bank does not support any operating systems other than Windows and MacOS. The Netbank service is based on a Java application and uses the browsers 128 bit encryption engine for secure transmission. I had Netbank working with earlier version of Netscape that had been fortified to enable US domestic level of encryption.
  The Java Virtual Machine in netscape for linux is fragile to say the least. Most problems can be cured by removing ALL trace of netscape from your system and installing the lastest version from scratch.
  Most problems are related to the browser, however Linux 2.4 introduced a new variable - the Linux IP stack in 2.4 contains a new feature called 'Explicit Congestion Notification'. It is on by default. Some firewalls and packet filters throw away packets with unknown bits set, and the Commonweath Bank (or more accurately their computer outsourcing company, EDS) have a firewall the drops ECN enabled packets with out trace.
  Attempts to get CommBank to do any thing about this have proven futile. The email 'help' people responed 'call the help desk'. The help desk operator, while sympathic, was not a techie, and could find NO ONE that was interested in the problem, as Linux is not a supported operating system. I kinda feel sorry for her, she tried.
It looks like that until some version of windows also gains ECN support, the problem will not be addressed. The CommBank are cutting off from their service an entire group of users completely unnessesarly due to this strict rule applied to their support centre. If word actually got down to the people on the ground that their packet filter rules needed updating the problem would in all probablity be fixed rather quickly.
  Fortunatly ECN can be turned off.
echo 0 >/proc/sys/net/ipv4/tcp_ecn  
after which I can use netbank fine.

Linux (unix) requirements for NetBank

  There is an 'interesting' netscape feature with Java/Javascript. To run the NetBank java application all that appears to be needed is JavaScript. It would appear even with Java turned off, a piece of JavaScript can load the JVM and get code to run...
  This page exists only so that other Linux users / Comm Bank customers can get some info. The M$ centric bank won't help.