Many character is difference between the 6u10 b27 and 6u10 b31

There have some difference between the base build (6u10 b27) and test build (6u10 b31). The FontEffectTest_ar.png is a example picture of testcase swing/FontEffectTest_ar. You can refer to http://java-g11n.sfbay.sun.com/j2se/gate/report/6ur/results-automation/1.6.0_10-rc2-b31/mustang_gsms-SunOS5.11i38664_ar_EG.UTF_8-1.6.0_10-rc2-b31/GlobalSuite-Report.html for more fail testcases and details.

The bug is produced on RedHat_x86-5-ar_EG.UTF-8, RedHat_x86-5-ar_SA.UTF-8 ,Solaris_amd64-11-ar_EG.UTF-8, Solaris_amd64-11-ar_SA.UTF-8.