Vacuum Problems

I need some help or just some hints. I am having problems with vacuum full in one table only: "clifatura".

That table has today around 7 million rows.

I scheduled on the server a cron job to run VACUUM FULL every day at 23 P.M, but on the following day, at 8 A.M. vacuum is yet working on "clifatura"; so I have to kill vacuum.

I read something about maintenance_work_mem, so I increased it to 128MB. My server is a Intel Xeon Dual-Core 2.8 Ghz with 2 Gb RAM, running Postgres 8.2.4.

In others times recreating the table is Ok, but it can't be the right thing to do.

I hope anyone have some information.

Thanks,

Rafael Domiciano