Database Software

Hello folks,
A couple of days ago, I finished importing an oracle DB. I used the impdp command and got few errors after the import was done. Please, find below few error details which were taken from my log. I've managed to solve few errors but I don't know what to do with this type of error:

ORA-39083: Fallo de creación del tipo de objeto SYNONYM con el error:
ORA-00995: falta el identificador de sinónimos o no es válido
El sql que falla es:
CREATE PUBLIC SYNONYM "ST_INTERSECTS" FOR "SDE"."ST_INTERSECTS"
ORA-00995: falta el identificador de sinónimos o no es válido
El sql que falla es:
CREATE PUBLIC SYNONYM "ST_INTERSECTS" FOR "SDE"."ST_INTERSECTS"
ORA-00995: falta el identificador de sinónimos o no es válido
El sql que falla es:
CREATE PUBLIC SYNONYM "ST_LINESTRING" FOR "SDE"."ST_LINESTRING"
ORA-00995: falta el identificador de sinónimos o no es válido
El sql que falla es:
CREATE PUBLIC SYNONYM "ST_MULTICURVE" FOR "SDE"."ST_MULTICURVE"
ORA-00995: falta el identificador de sinónimos o no es válido
El sql que falla es:
CREATE PUBLIC SYNONYM "ST_MULTILINESTRING" FOR "SDE"."ST_MULTILINESTRING"
ORA-00995: falta el identificador de sinónimos o no es válido
El sql que falla es:
CREATE PUBLIC SYNONYM "ST_MULTIPOINT" FOR "SDE"."ST_MULTIPOINT"
ORA-00995: falta el identificador de sinónimos o no es válido
El sql que falla es:
CREATE PUBLIC SYNONYM "ST_MULTISURFACE" FOR "SDE"."ST_MULTISURFACE"
ORA-00995: falta el identificador de sinónimos o no es válido
El sql que falla es:
CREATE PUBLIC SYNONYM "ST_OVERLAPS" FOR "SDE"."ST_OVERLAPS"
ORA-00995: falta el identificador de sinónimos o no es válido
El sql que falla es:
CREATE PUBLIC SYNONYM "ST_POINT" FOR "SDE"."ST_POINT"
ORA-00995: falta el identificador de sinónimos o no es válido
El sql que falla es:
CREATE PUBLIC SYNONYM "ST_POLYGON" FOR "SDE"."ST_POLYGON"
ORA-00995: falta el identificador de sinónimos o no es válido
El sql que falla es:
CREATE PUBLIC SYNONYM "ST_RELATE" FOR "SDE"."ST_RELATE"
ORA-00995: falta el identificador de sinónimos o no es válido
El sql que falla es:
CREATE PUBLIC SYNONYM "ST_SURFACE" FOR "SDE"."ST_SURFACE"
ORA-00995: falta el identificador de sinónimos o no es válido
El sql que falla es:
CREATE PUBLIC SYNONYM "ST_CONTAINS" FOR "SDE"."ST_CONTAINS"
ORA-00995: falta el identificador de sinónimos o no es válido
El sql que falla es:
CREATE PUBLIC SYNONYM "ST_CURVE" FOR "SDE"."ST_CURVE"
ORA-00995: falta el identificador de sinónimos o no es válido
El sql que falla es:
CREATE PUBLIC SYNONYM "ST_GEOMCOLLECTION" FOR "SDE"."ST_GEOMCOLLECTION"

I would appreciate your help understanding what does this frequent error means, and whether there's a solution available.

Thanks!

Database version 11g
OS: Windows 7 which is supported by Oracle. I recently cheched it and no incompatibilites with regard to the OS.
Command to do the import: "user/password" full=y DIRECTORY=export DUMPFILE=expdp.sgtc.01052012.dmp logfile=impdpPRACTICANTE.log
Before import the user was granted priviledges as well.
The database was recently created and the software has recently been installed too. Never used it before but I manually created 20 tablespaces and 317 users.

Any reply is a supply!