What's happening with this process (ps & strace logs provided) ?

[Xanana Gusmao]

I have a "java" process that is hanging.
I did a strace on it and it spat out a one liner:

  futex(0x21yjh982, FUTEX_WAIT, NULL , ...)

The ps output on the process follows:

SIZE  RSS  SHARE   %MEM
947M  661M  540     68

Base on this meagre amount of information, what can you deduce ?

Regards,

Xanana