Oracle 8.1.7.4 Enterprise on HP-UX 11.0

Is anyone aware of problems with bitmap indexes when the cardinality is high (hundreds or even thousands of unique values)
As bitmaps were meant for low cardinality, I know that high cardinality columns should not be candidates for bitmaps but I need to know if someone does create such indexes what issues may pop up?

Here are the issues I had so far with bitmap indexes and that's why I started looking closely -

1. One of my developers was using Function based indexes (6 months ago) and so set the QUERY_REWRITE_ENABLED parameter to TRUE. This started causing some issues later on with ORA-600 and Oracle support recommended rebuilding the bitmap indexes (they said that other people had faced similar issues with bitmap indexes and rebuilding often would help)

2. We started getting some more Ora-600 issues (after patching to 8.1.7.4 from 8.1.7.0) and this time Oracle support said that we had hit a bug 2767505 and the solution is to drop/recreate all relatted bitmap indexes before DML or go to 9.2.0..4

Looking at the bitmaps I see that some of them have 100,000 unique values out of 6 million records; so the cardinality is less than 2% but still very high.

Just wondering if any of you had such issues with high cardinality (if I can call it that)

Thanks,