concurrent reindex issues

Hey all, it's been a bit however I'm running into some issues with my
concurrent index

Always get this error during a concurrent index.

*2009-10-07 22:18:02 PDT admissionclsdb postgres 10.13.200.70(46706) ERROR:
deadlock detected*

*2009-10-07 22:18:02 PDT admissionclsdb postgres 10.13.200.70(46706)
DETAIL: Process 20939 waits for ShareLock on virtual transaction
16/43817381; blocked by process 1874.*

* Process 1874 waits for ExclusiveLock on relation 17428 of database
16384; blocked by process 20939.*

*2009-10-07 22:18:02 PDT admissionclsdb postgres 10.13.200.70(46706)
STATEMENT: CREATE INDEX CONCURRENTLY prc_temp_idx_impressions_log_date2 ON
tracking.impressions USING btree (log_date) TABLESPACE trackingindexspace*

This happens all the time, so it's not the occasional deadlock. We even
turned off all applications that insert into the database and it still
fails.

Tried restarting the database as well.

Also when looking at active connections there is no process 1874.

So I'm at a lost, this first started happening in my slave DB (Slon
replication), but it is now happening on my master which is odd.

Any idea?

postgres 8.3.4

Linux system.