<p>Is it possible to use oracle instant client for application that use oraoledb driver for connecting to oracle 9i DB.</p>

I don't believe so.  The
Instant Client FAQ
states
What can Instant Client be used for?
  Instant Client can be used to run your OCI, OCCI, Pro
C, JDBC, and ODBC applications without installing a full Oracle Client. In addition, Instant Client supports SQL
Plus. As of Instant Client 10.2, it is also possible to develop applications for OCI and OCCI using the Instant Client SDK download.
OLE DB is conspicuously absent from that list.  Now, potentially, you could use the Microsoft OLE DB to ODBC provider along with the Instant Client and ODBC, but adding additional layers to software is never very fun.