I am having the same problem when exporting from 11g R2 and importing into another 11G R2 instance. The issue appears to be on import on 11G. I'm going to open a premium incident on this..
Thanks Vishal. I tried again using the method recommended above and got the same exact errors as before. Also, one of the errors listed in the KB is not the same as the one I'm getting. I get the first two it lists, but I don't get:
ORA-39779: type "SDE"."ST_GEOMFROMTEXT" not found or conversion to latest version is not possible".
Instead, I get the following (note the different function):
ORA-00600: internal error code, arguments: [kpudpxcs_ctxConvertStream_ref_1], [SYS_TYPEID("SHAPE")], , , , , , , , , , 
So there is something different going on. What do you advise?
After upgrade from ArcSDE 9.2 (Oracle 10.2 g) to ArcSDE 10.2.2 (Oracle 12c) there was problem by ST_GEOMETRY spatial index export with datapump. This script resolves the problem.
There were a few issues in 11.2 related to datapump that you could be running into. This one looks like a possibility:
There is another mentioned here: