(fs) Files.probeContentType reports a MIME type of "text/plain" on Ubuntu 11.04

Test machine: sc11136070

Below test case fails on ubuntu only. It works well on Solaris
java/nio/file/Files/probeContentType/Basic.java

Command:
/net/koori/onestop/jtreg/4.1/promoted/latest/binaries/jtreg/linux/bin/jtreg -a -va -nr -w:$HOME/temp -r:$HOME/temp -jdk:/net/koori/onestop/jdk/8/latest/binaries/linux-amd64 -timeoutFactor:5 /net/koori/onestop/jdk/8/latest/ws/jdk/test/java/nio/file/Files/probeContentType/Basic.java

Log:
java.lang.RuntimeException: Unexpected type: text/plain
at Basic.main(Basic.java:64)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:474)
at com.sun.javatest.regtest.MainWrapper$MainThread.run(MainWrapper.java:94)
at java.lang.Thread.run(Thread.java:722)

JavaTest Message: Test threw exception: java.lang.RuntimeException: Unexpected type: text/plain
JavaTest Message: shutting down test

STATUS:Failed.`main' threw exception: java.lang.RuntimeException: Unexpected type: text/plain

TEST RESULT: Failed. Execution failed: `main' threw exception: java.lang.RuntimeException: Unexpected type: text/plain