In the JDK6 javac reports about encoding warning however now it reports about error like this:
/net/vmsqe.russia/export/jdk/re/7/promoted/ea/b70/binaries/solaris-i586/bin/javac /net/vmsqe.russia/export/testbase/jtreg/7/HS_REGRESSION/test/closed/runtime/4948258/NativeImageTest.java

Output ends with:

/net/vmsqe.russia/export/testbase/jtreg/7/HS_REGRESSION/test/closed/runtime/4948258/NativeImageTest.java:114: unmappable character for encoding UTF8
                                        // System.out.println(getDateTime()+"¿F¿¿F"+getName()+"¿Fadd");
                                                                               ^

I did not find any CR related with this change. So if this is not a bug but a feature please change state to incomplete and I reassign it to the test.
Test name:
closed/runtime/4948258/NativeImageTest.java
This is a bug in the test, it should be updated to be compilable.