JCK: JCK-runtime-6a alt. bundle
J2SE: FAIL - 6u5p b01, PASS 6u5,  6u4p
Platform[s]: FAIL -  All
switch/Mode: FAIL - -server -Xcomp

Test api/java/text/NumberFormat/Format has side effect since 6u5p b01. For example:

java -server -Xcomp -Xfuture -classpath K:\\Links\\stt\\jck_promotions\\6a\\fcs\\alt2\\binaries\\JCK-runtime-6a\\classes javasoft.sqe.tests.api.java.text.NumberFormat.FormatTests -TestCaseID NumberFormat0010

test reports:
NumberFormat0006: Passed. OKAY

passes. At the sampe time when run after another test it fails:
java -server -Xcomp -Xfuture -classpath K:\\Links\\stt\\jck_promotions\\6a\\fcs\\alt2\\binaries\\JCK-runtime-6a\\classes javasoft.sqe.tests.api.java.text.NumberFormat.FormatTests -TestCaseID NumberFormat0006 NumberFormat0010
NumberFormat0006: Passed. OKAY
NumberFormat0010: Failed. Failed
Method format(Object, StringBuffer, FieldPosition) incorrect
StringBuffer passed to format(Long, StringBuffer, FieldPosition) method
  expected value of StringBuffer =
  passed value  =
STATUS:Failed.test cases: 2; passed: 1; failed: 1; first test case failure: NumberFormat0010


Test does nothing except assigning one StringBuffer instance to a member of class NumberFormatTest then comparing both objects with ==. 



Steps to reproduce:
run commands above. 
Unix path to JCK is:

/net/stt-13.russia.sun.com/export/stt/jck_promotions/6a/fcs/alt2/binaries/JCK-runtime-6a/classes
test sources:
/net/stt-13.russia.sun.com/export/stt/jck_promotions/6a/fcs/alt2/binaries/JCK-runtime-6a/tests