Objective - conversion from sybase database to oracle database.

sybase database version 11.5
oracle version 8.1.7

sybase sql to oracle sql /plsql
sybase tables, views to oracle tables , views
some stored procedures to be converted to oracle proc.

1 is there ay tool in oracle which can do these conversions.
2 any one who has done this can u please tell me how did u
do this
3 if not 1 or 2 then any link /web site where i can get the
conversion procedures

Thanks in advance