Oracle Database Discussions

We have a tablespace that has become full (ORA-01653: unable to extend table xxx by 64 in tablespace ODI_WORK)

There is about 24GB of recycle-bin objects in that tablespace.
According to the Database Administrators Guide (http://docs.oracle.com/cd/E11882_01/server.112/e25494/tables011.htm#sthref2311) says:
Dropped tables and any associated objects such as indexes, constraints, nested tables, and the likes are not removed and still occupy space. They continue to count against user space quotas, until specifically purged from the recycle bin or the unlikely situation where they must be purged by the database because of tablespace space constraints.

So, we have apparently reached the space constraints; why were the objects not purged?

select * from v$version;

BANNER
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Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
PL/SQL Release 11.2.0.3.0 - Production
CORE 11.2.0.3.0 Production
TNS for Solaris: Version 11.2.0.3.0 - Production
NLSRTL Version 11.2.0.3.0 - Production

5 rows selected.

Thanks,
Mike