It seems you are using the function described here:
Apparently the required object type t_string_agg is missing on your system
It is missing.
I have taken the data backup through export and imported to this particular function to new user and it was not imported and given error.
import done in WE8MSWIN1252 character set and AL16UTF16 NCHAR character set
. importing PAMS's objects into PAMS4NINE
IMP-00017: following statement failed with ORACLE error 2304:
"CREATE TYPE "T_STRING_AGG" TIMESTAMP '2012-05-11:15:27:23' OID '98013589951"
How can i import this feature to my user
Thank you sir
I don't know why your import fails, but you can find the source code of the object type on the page I have posted.