It's the old divide and conquer school of DBA security. Only the SA can see the core dump. However, I assumed that there was a reason you sent me there and a bit of searching did find BUG 4695511 which seems to fit the bill.
*ORA-600 [KXFQUPP_BAD_CVL] WHEN CREATING BITMAP INDEX ON HUGE TABLE * ** The work arounds are "don't do that", increase the degree of parallelism (we don't know how much - try doubling it and see if that works) or apply a patchset.
I have passed the information along to those who will decide on the appropriate response. I expect that our work around will be to not use parallelism since that will only inconvenience the end users.