The following is an e.mail snippet from SAP, who are facing grave issues between the JDK versions 1.4.2_17 and 18. The issue is currently processed by Kevin Walls, who has already invested considerable time with the issue and provided solutions towards the issue. I'd therefore like to request this issue to be processed further by Kevin.
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-XX:CompilerThreadStackSize was ignored in previous 1.4.2 Windows versions. -Xss was recommended as workaround (bug-id 6579892 ).Starting with 1.4.2_18 the parameter is used now AND -Xss is ignored for the compiler thread, even if -XX:CompilerThreadStackSize is not set.

Therefore existing systems and our installation procedure run with 1.4.2_18 in stack overflows because we use -Xss to set the (compiler) thread stack size. Of course we could write hints for the customers and recommend -XX:CompilerThreadStackSize to solve the problem. But a JDK switch is a common thing, so that probably a lot of customers will do the switch without reading the notes. Additionally for installation customers have do do some manual changes of files, which might cause trouble.

Hence we expect a lot of problems at customer side when they switch to 1.4.2_18 or above. Therefore we would ask SUN to fix the -XX:CompilerThreadStackSize issue in a compatible way, which would mean that -Xss is used for the compiler thread too if -XX:CompilerThreadStackSize is not set.
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